How Data Recovery Works

our podcasts have been a failure to communicate. That's true, okay, but we've gotten better, uh in some people's eyes. So let's tackle this topic. What are we talking about today, Chris, We're talking about hard drives, or possibly the lack thereof, depending on what happened to them. I got you now, We've already done a podcast about hard drives. It actually

wasn't that long ago. But one thing we didn't really touch on is how do you get data off a hard drive if the hard drive has suffered some some problems, if it has crashed in some way or another, and uh, really to get this out of the way, depending upon the severity of the crash, there may not be anything you personally, as in the average customer or average user can do to recover that data. Doesn't mean that there's

no way to get the data back. It just means that, depending upon the severity and nature of the crash, Uh, it's better to hand it over to a professionals. And we'll get into why. Um, but let's go ahead and talk about the fact that there are two major categories of hard drive failures. There are logical failures, which I suffer on a daily basis, not through my hard drive,

just me by myself. Um. And logical failures that's when your hard drive suffers some sort of corruption or there's a logical error where the computer cannot recognize the drive, can't access the information that's on that drive. Yeah. If you've ever had had files go corrupt on you, that's sort of like what's going on here. Your operating system can become corrupt and in a lot of cases it basically well, we can get into the details of that later,

but that's that's what's going on. You can't you can't read files on it. Yeah. Um, And this can happen from either again, as Poletts said, like a file, a file becomes corrupted. Uh, you could get a virus that does this sort of thing. Um, there are a lot of nasty malware out there that kind of does this to your hard drive. Uh. And as a result, your your system bios may recognize the drive, but it's not going to boot it, and then you're gonna think, okay,

well what are my options? Uh. So that's one type of failure. The other type of failure is a physical failure of the drive. Now we're mainly talking about, um, the platter based hard drives here, not the solid state. Solid state can also suffer physical failures. Uh. Physical damage that as a result of things like being exposed to magnetic fields, are actually suffering physical damage. But it's a different,

different kind of damage than the platter based hard drives. Right, just as a refresher if you didn't listen to the hard drive podcast or have forgotten. In a typical traditional hard drive, you've got a mechanism that is spinning platters. And Uh, in addition to that mechanism that is spinning platters, there is a head that is a very very very minute distance apart from the platters. It doesn't actually touch

the platters read and write to well. No, I mean and in a typical operating, normally operating hard drive it is it is there to read and write information to it, but it does not touch the platters. Now, if the drive mechanism breaks down, if the pins the connectors that connected to your computer break um, if the head actually touches the platters, which is known as a head crash. Um. If any of those things happens, you can suffer a mechanical failure to your hard drive and your computer may

no longer be able to operate that device right. And mechanical failures happen for many different reasons. Uh. It could just be from physically moving a computer around and you've jostled something loose. It could be just the fact that you know it's mechanical. Things are moving over and over and over, and if you have something long enough, those parts are going to start to have wear and tear

and eventually will break. Or it could be that your computer perhaps is generating too much heat and the heat in turn is expanding the elements within your hard drive and that is what's causing stuff to uh to to not operate the way it's supposed to heat bad for hard drive. Heat is not a good thing. And of course they generate them because they're mechanical, yes, and then

they're you know the whole friction thing. Yeah, yeah, so and I. In either case, you're going to have a situation where you're not going to be able to access the information that's stored on that hard drive. And depending upon the severity of the problem, either with a logical or a mechanical issue, you may or may not be able to retrieve this data on your own. There are a lot of different kind of do it yourself things you can attempt, depending upon the type of problem you have.

Let's say that you have a logical problem, for example, with your hard drive. Um, if you are fairly adept at handling computers, you know you know the ground yourself before you touch anything inside a computer, for example, and that you don't feel ill at ease messing around on the inerts of a computer. And this mainly applies to desktops. Laptops are a lot harder to to do do it yourself projects on just because the way they're constructed, especially

for people who are less experienced with those projects. Yeah, some of them require special tools just to get the case open, because they're using proprietary screws to hold them closed. My fears always how do I get everything back in it the way it came? YEA for those of us who had the kind of childhood where we um took stuff apart to see how it worked, and then realized that when we put it back together it was never going to work again. We get nervous when we start

opening up computers. But you may be able to remove the hard drive, not open up the hard drive case. Never ever ever open up the hard drive case, well at least not if you expect it to ever work again. Right. If you want the data that's on that hard drive, you will not open it. I mean, okay, if you have a clean room and you are trained to do this kind of thing, and you're a data recovery specialist,

sure then you can open up the hard drive. But for everybody else, do not do it right because those platters on the on the physical hard drives, the platter based hard drives, um, if you get any dust on that, it can it can cause that data to to be inaccessible forever. You don't want to get dirty. You don't want to get scratched. You don't wanna. I mean, there are chances that you could clean it or have someone

clean it and get that data back. But just in the process of trying to read that that platter, you're going to find out that you can't get the files that you thought you were gonna be able to get just because they got dirty, right right, Well, you know that that's do you want to keep going with the logical stuff with the mechanical stuff because I was I have a good bit of information on how they they get that information back on a mechanical drive, but I

don't want to get into that. Let's do Let's go with mechanical first, because the mechanical, depending upon again the severity, you may be able to do some stuff yourself. Here here, here's something that you could potentially do with a mechanical failure. Now that this is a mechanical failure where uh, I'll give you three different examples. Here's one where your your drive is spinning. Here it's spinning, but there's a clicking noise,

something is hitting against something else that's not good. Here's something that you may have heard that you can do. You may have heard that you could put your hard drive in the freezer. Yes, I have heard that you can do that. I mean, granted, obviously you can do that. Assuming there's room in your freezer. You could do that. And actually, the surprising thing is this can work. Uh.

Of course would have to remove it from the computer first. Yes, yes, okay, there are some intermediate steps removing it from the computer, putting it into a ziploc bag so that you don't get any condensation on your hard drive, um, and then putting it into the freezer for around twenty four hours. The reason why this might work, this, by the way, does not fix the drive. It's just a temporary measure so you can get the data off the drive onto

something else. The reason why this works is because the cold will cause the various components within the hard drive to contract. So if it if the reason why it's it's hitting against stuff is because something slightly out of alignment or heating has caused things to warp a little bit. Contracting may cause it to get close enough back to the original positions for it to run for a short period of time and I'm talking like half an hour max.

So with that in mind, if you've if you could put your hard drive in the freezer, and you have it set up so that you'r you can capture the data that's on that hard drive, either using another computer or your first computer with a new hard drive in it. Whatever, you can give that a try. You can hook the hard drive back up to a computer, boot it up and see if it's running, and it might run fine. Um, but it's not gonna run fine for very long because as soon as it heats up, it's gonna start warping

again or or breaking down. So you only have a route about, like I said, thirty minutes maybe maximum to get the data from that hard drive onto a different storage device. Uh. Here's something that I feel that we should mention. What's that that? Um, when we're talking about these home remedies, keeping in mind that you know, if

you try this, you're trying it at your own risk. Yes, we do not recommend doing this and saying that it's going to to fix everything and you're going to be able to get your You will absolutely be able to do this successfully without any problems. There's a good chance that you may not get anything from these home remedies, But the reason that people try them is to avoid

paying the very large fees the data recovery services charge. Yeah, as it turns out, like because because to do data recovery right quote unquote right to the point where you know you're going to get you know, over the data back. Uh, it's it's a complicated and technical process, and so it does cost a pretty penny. Um is not an unusual fee to see in in data recovery services. Is at

an unusual fee to see in data recovery services. But did you want to keep going with the one more home rent or well, kind of like you do a combo home renmedate. Let's say that you're hard drive is not spinning, so it won't spin up right there? There is a a method where that you can try, if you're brave to uh, to see if you can get it spinning again, which is, again remove the hard drive from your computer, and then use what I like to call the Fawn's method. You give it a whack with

the palm of your hand a rubber mallet. Maybe you drop it from just a few inches above the table, and that might unstick whatever is stuck inside your hard drive. I don't recommend it, but it is it has been known to work. It has been known to unstick elements that have caught together within hard drives. And again it's another method where it's a temporary fix. You need to get that data off a SAP. Uh So, yeah, that's

the the hit and or drop method. Those are the three do it yourself methods for mechanical failures that I happen to know off the top of my head. Okay, well, um, you may be saying, okay, so a minute ago, you you guys were talking about the data recovery services. Well, what did they do that so special? Lets them charge

that much money for it? A lot of the data recovery services out there, Um, when you take your drive to them when it's busted, you know that it's a mechanical failure going on because you hear the clicking noise, or it won't spin up, and or you can see that the pins have been damaged and you need to get the information off of there, perhaps as soon as you know right now. Um, this is where the data

recovery services shine. And there may be somebody in your hometown or maybe somebody that you need to mail it off. Uh two. But the thing is what they're gonna do when you do that is they will They will probably charge you a small fee, maybe hundred dollars, maybe even nothing. Maybe they'll do it for free. But what they'll do is they'll evaluate the drive to see whether or not

they can actually do anything with it. If they think they can work with it, they'll let you know, and they'll let you know approximately how successful they think they'll be. And what happens is when you say, okay, yeah, go ahead and pull all the data off of there. They're not going to repair the drive for you. There's not going to be a lot that they can do in

the event of a mechanical failure. Like Jonathan was saying just a moment ago, there's there's only so long that that drive is going to work in its current state, if it will work at all. Um So, what they're going to do is a very good data recovery service is going to have what they call a Class one clean room. Yeah, this is a room that filters the air so that there are fewer than a hundred particulates floating around inside that room, no bigger than half a

micron in size. We're talking a very very clean clean room. And so you've heard us talk about clean rooms before, because we chatted about it when we were talking about building chips like microprocessors. The fact that you need that because the elements on these chips are so small that a moat of dust dwarfs them, and therefore, if it gets on you know, some silicon when you're about to process press press eight chip, it's going to ruin that chip. Yeah,

same sort of thing here. You know, you can't get these things. If you want to be able to retrieve the data from these these crashed hard drives, the platters have to be clean, yes, And I mean if you're trying to if if they're trying to get your data back and you've had a head crash and their actual gouges in the surface of the platter um adding dust to it, it's not going to help anything. You're just

gonna make their job even even more difficult. So they're going to take the drive apart in a clean room, and what they're gonna do is they're going to examine it to see what's going on. So if the drive mechanism is bad, they're going to move the platters to uh a mechanism that will work so that they can get the information off of their and enshort. What they're gonna do is they're going to retrieve the information and you know, burn it to a disk for you so

that you can retrieve the information. Your hard drive is shot, but um, it sort of depends on what's going on with it now. Jonathan was also talking about getting stuff on it. If your drive has been submerged in water or you know, caught in a fire. Say you're your fan stopped working in your desktop computer and it started a small fire. You put it out, but your hard drive got caught in there. Maybe it's only suffered you know, a little smoke damage, but you still can't use it.

They're going to have to take the platters out and clean them very carefully with the with the solution that they use for that kind of thing, something that's not going to affect the readA or right ability of the platter I guess, and put it in a mechanism again that that will work. Uh, and do that now. And when we say mechanism a lot of these hard drives, what you have to do is have an identical working hard drive. Because hard drives come in different shapes and sizes,

they come in differently. You know it's and it's just one of those things where it's not like they have a universal device and you put a platter in there and it's gonna work perfectly. That's another reason why it's so expensive for these for these businesses to work properly, they need to have spare parts from lots and lots

of different uh hard drives. Um. One of the other kind of physical failures, which you know, I didn't really chat about because again I was focusing on the do it yourself, and this is really not to do it yourself, is an electronic failure where the circuit board beneath your hard drive, the thing that connects the connecting point between your hard drive and your actual computer, the physical connecting point that can have a problem, that can suffer a failure,

in which case you really need someone else to fix it, like to give you an identical circuit board and connect it all together properly for to to come back, and you may not even be able to do that. That computer might be shot or you may have to rebuild from that that point on, in which case data recovery is really your only, your only option to get that information back anyway. You're not gonna you know, it's not

necessarily repair thing, it's a recovery. So uh. Again, if you take it to a data recovery specialists, they're going to have to have those parts in stock to be able to to do anything, because again it's not a one size fits all sort of model. Everything's proprietary. Yeah.

The most the most serious problem that you could have as a mechanical failure, I would say, is when there's actual physical damage to the platters themselves, the likelihood of getting information back off of that that disk is less than a lot. It depends on It depends on a lot of different factors, how bad the gouges are and where they are on the disc, and how good your

data recovery specialist is. There's some data recovery specialists out there who have men age to retrieve data from hard drives that I would have sworn were beyond the ability to to salvage UM. And you actually had a really good example of that. You send it to me about

the uh, the hard drive recovered from a Space shuttle. Yes, the Space Shuttle Columbia, which, as many of you will remember, UM had a a problem that caused it to burn up on re entry and it broke apart, of course, killing me the astronauts on board unfortunately, and UM, of course, a lot of the parts were recovered. A lot of the pieces of the shuttle were recovered, including at least three of the hard drives, and UM NASA sent those UH to one of the giants in the industry and

all on track UM to have them recovered. Now, two of the drives that that were mentioned in this MSNBC article UM they had a whole media section with lots and lots of articles about what they do UM, as as many good marketers will do UM. But they had an the article on MSNBC U it was really fascinating because two of their hard drives were burned so badly

that they really couldn't do much with it. Another one, however, UM had suffered a had suffered damage to the platters, but they were able to clean the platters off and get the information, not because UM, you know, the gouges weren't significant, but because the data had stopped writing short of where the gouges were, so that the data was intact up to the point where the gauges started. The undamaged part of the platter. It was the part that actually had data written to it was the damaged part.

No data had been written to that section yet. And you may remember in our hard drive podcast we talked about how when you write information to a hard drive, it doesn't necessarily do it sequentially on the platter itself. So you're trying to you're not necessarily gonna have two sectors next to each other containing one really big file. Well, in that particular instance, you did because they were using sauce,

which has a different way. I mean, it actually stored data sequentially on the hard drive, so it wasn't saved. Willy nilly, I'm sorry, I keep talking. Every keep just interrupting. You keep going, please, um no, No. That That's the thing about about that is that in this case they were the drive recovery specialists who were able to save information that the scientists said can had conducted while they were out in space. So that was a very very

positive outcome for that particular instance. But unfortunately, the other two drives were damaged beyond repair, and that you know, is certainly not unheard of even for the best of the best. Right, Yeah, if the if the platters have suffered real severe damage, then there may be nothing you can do. Um, you mentioned flooding. I was gonna point this.

This is not really a do it yourself but this is one of those things that it's good to know in case you ever are in a situation where, uh, you have a hard drive that's been submerged in water, but for you take it to a specialist, you may want to continue to have it submerged in water. Really yeah, here's the reason why. Uh. When the water gets into the hard drive, it can be caring, carrying lots of

particulate matter along with the water. When that hard drive dries out, that particulate matter can adhere to the platters on your hard drive. I see. So that can make it more difficult to clean the hard drive and makes it less likely that you're going to get all your

data back. Um, if you submerge the hard drive in water, that can keep the particulates uh kind of suspended in the solution of the water, and you can take it to the recovery specialists who can then in a very controlled manner, remove the hard drive, dry it out, and clean it so that it's these little particulates don't get stuck to the platters. So what you're saying is if it's if it's still submerged in water, keep it still

submerged in water. Yeah, yeah, because I would assume that if it had been you know, if you had had a flood in your house and you would evacuated, the water was gone, everything was dry ish. Yeah, if you come you're probably the damage is probably if you come back and it's and it's already been dried out, then there's not really any point and you submerging it again because if it's those particulars have adhered to the platter, there's very little likelihood that they're going to to detach

once you submerge it back in water. So no need to to go to that step. But if it is submerged in water, you may as well continue to do that. You know, it's again anytime there's gonna be water and electronics, you have to be really careful. There's always the danger of electrocution. But you know, assuming you're able to get the hard drive out safely, uh, it is not a bad idea to go ahead and keep it submerged in water until you can get it to a recovery specialist.

The damage has already done. Really yeah. Yeah, Now, a data recovery specialists can also help you with a logical hard drive failure, although they may not need to. There may be some things that you can do yourself. Right, So, if you've got a corrupted file system or you've got a virus on that hard drive, uh, sometimes you can remove that hard drive from your computer, put it in say an external case, and connect it to a working computer.

If you have the right software, you may be able to scan that hard drive and be able to without going into any further detail, you might be able to just pull the data directly off of it and put it onto another storage system. Uh. That's the best case scenario. Really. Yeah,

you might also might be able to. Uh. It's also not a bad idea to keep an emergency boot c D around too, which would would help you with that too, because if you have UM one of the major anti virus UH utilities and those types of the computer utilities discs, they'll let you burn a CD ROM or DVD. I guess that would allow you to boot up your computer and it would run off of the disk, allowing to scan your hard drive and make sure that it isn't in any way corrupted or that it's got a virus.

They may be able to fix it that way. But um, you know, in generals, a lot of the problems that come from this is uh, from the pointers that go to the files. I mean, that's what happens. When you delete something, You're you're basically racing the pointers to the file, and that allows the sector to be rewritten, you know, when you do something else. But if the file hasn't been written over and the pointers are missing, those can

be re established. Right. Yeah, that's a good point. Um, when you delete something from a hard drive, it's not really gone yet, right. Um. It's essentially when you delete something from your hard drive, you're essentially giving your computer a direction saying this data is no longer important to me, so the next time I am writing data, this space

is available to be written over. Um. It's so there's even a chance if you've deleted something, if you haven't written anything new to the hard drive, there's a good you can recover that. Saying there's a chance, I mean you can recover that. But if you've started to write stuff to the hard drive again, like you've saved a new program to the hard drive, there's a chance that the sectors that contained the data from that file you accidentally deleted were some of the sectors that they got

written to. So UH, that's one thing I wanted to to mention too. We were talking about the software that allows you to scan uh your hard drive to to correct any file corruption or to try and find files. UM. This software can be pretty expensive. Again, like is not unusual for the kind of software that that does a pretty good job at uh at looking for files on a corrupt logic problem on a hard drive. And and

they're specific to different operating systems. So you know, the Windows operating system, the Linux, the mac os all have different UM software for those and at different price points. You want to be careful when you choose a recovery software package because if you if that recovery software package in turn rights to the hard drive as a part of trying to scan it, uh, that means you could lose data because it's writing over something that's already there.

Once you write over it it, I'm not gonna say it's impossible, because lord knows, I'm not gonna say it's impossible to get the data back if you overwrite it. Uh. Because every single time someone says that something pops up where it becomes an exception to the rule, but it is immeasurably more difficult to get that data back right.

And that's something to keep in mind too. If you're intentionally trying to delete stuff thinking that the cops will never find it, yeah, they might be able to because it drive recovery specialist can probably get it back. You pretty much have to delete everything right over every thing

deleted again, right over it again. I mean, they're there are people who are experts at getting rid of data where you're doing it electronically and you're not just determined to destroy the hard drive because you can always do that well, they said. Even the information I got when I was doing research suggested that even you know, taking a pair of pliers to a platter may not damage all of it, I mean, which is why magnet would help. There was that one if you're trying to destroy it,

there was that one company that we saw. I don't know if you were, I don't know if this was one of the years that you went, but at CES there was a company that specifically specialized in destroying hard drives so that the data was not recoverable. Um and they had a couple of different methods, and one of them was that it would just punch an enormous hole through the entire hard drive using a essentially an industrial sized drill press kind of thing. Even then you might

be able to find it. But there was another one that would tread the platters. Yeah, that one pretty much do it. That does it. Yeah, you're it's gonna be really hard to get any information out of a shredded platter, Yeah, I wine, so yeah. If it's a if it's a logic problem, usually there's some sort of software that you

can use to attempt to get at that data. Occasionally, the problem is going to be so specific or so unusual that that unless you have exactly the right program, you're not going to be able to do it yourself. And again you may have to take that into a data recovery specialist who will use their own software to scan and image your hard drive and then dump all

the stuff. You should also know that if you're using the these um software packages, a lot of them, when they pull data off of your hard drive, are going to organize your data in big lumps so that it's not gonna be in the nice little file tree system that you had set up back when it was your hard drive and everything was hunky dory. Right, You're likely

to get a list of files. Right. You might get a full or that has all image files in it, which means that you're going to get a folder that has all the pictures you've taken and things like that, plus all the little image files from every single program you have on there. So it's all in a huge

disorganized lump. Uh, the same thing like all the all the document files will be together, you know, all anything that's a specific file type might be lumped together into a single folder, which, uh, that's really You're not necessarily gonna be able to use all the programs that you had before, but at least you'll be able to access certain you know, whatever files are at least easily findable in there, right, right, And I mean if it's something

that's that's truly important, especially for business reasons, Um, you know, they're they're just some things that you're gonna want to save period, you know, family photos there. You know, these things can't be replaced. So and uh, this is a good time for another reminder. Back up your hard drive always a good idea. Yeah, always. We We say it every single time we talk about any kind of hard drive issue. Back up your data, because things do go wrong.

I mean it's it's even if you're doing everything right, Systems can break down. Systems do breakdown. It's kind of this whole in tropic thing that we have going on in the universe. So you need to take precautions against it, and you know, treat your backup systems really well too, because backup systems could fail as well. I'm not saying that you have to make endless backups of your data, but always make sure you have at least one viable

one sitting around. Not a bad idea. Yeah, and uh, you know that might even involve saving to the cloud, because a nice thing about most cloud systems is a lot of them have built in redundancy, So the data that you save to the cloud ends up being stored on multiple machines because, just like any other machine, those servers can break down too. That's true. Well I think that did you? Did you have anything else to add? No? Not really, I think we we pretty much got into

most of it. Cool. So yeah, I hope all of you listeners out there never suffer a hard drive crash on the level that we're talking about here. Hopefully what will happen is you're all really really happy and wealthy, and then every time you get bored of a computer, you just go out and buy a new one, and that way you never have to worry about our drives getting old because you don't keep them long enough. And uh, if you have all this cash, why haven't you bought

us presence? That was a joke by corporate by corporate policy. I cannot accept any presence other than cookies because those were awesome. Yeah, So, if any of you have any questions, comments, you have a topic you want to suggest, you can

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