There you are, leaning back in your chair, the perfect business plan on the screen before you. How long had you worked on it? Seems like weeks. Now, it’s finished, and all that’s left to do is save it and print...
The only warning you had was a flickering of the lights and then the screen goes black and the computer goes dead. Worse than that, it won’t boot up again and over the next few moments the annoyance of a crashed computer gives way to that nauseous feeling of dread as it occurs to you that all the work — the sheer brilliance — that went into your business plan is now gone and you doubt you will ever reach those heights again.
That was one kind of data loss event. There are others that range from the accidental deletion of data to intentional deletion to natural disasters and criminal activity. That said, the most prevalent kinds of data loss are human error and hardware failure. These account for about 75 percent of the data loss events experienced every day and, as such, should be the first things to work on when developing processes to deal with the problem.
Gotta Love Modern Technology
The key to preventing data loss from mechanical failure is redundancy. That is achieved through backup copies of your data as well as properly storing those backups.
Backup copies of your data are essential. As intuitive as this may seem, it is important that your backup copy is not on the same drive as your original. Many people will backup their work on the same drive, thinking that it affords them protection if their original becomes corrupted. It does, but what happens if the whole disk becomes corrupted? Then everything is lost. It is important to put your backup copies on another storage device entirely. It can be a CD, a flash-drive, even another computer — anything that you can take with you and keep in a safe place. If the data is of particular importance, you may want to keep your backups in a fireproof safe.
Another kind of backup is the hard copy. Yes, old fashioned paper. Paper still has one main advantage over electronic storage — it doesn’t break. Just make sure it is properly stored and it will serve well as the backup of last resort.
Regarding the hard drive on your computer, that is where your data folders are. It is also where your operating system is, and that can be a problem because most of the issues you will have with your computer involve the operating system. Many times, the only solution is to reformat that disk and reinstall the operating system. If your data is on the same disk when that happens, it will be gone. Hence, as with the backup copies, you need to put your data on a different disk, be it a second hard drive installed on your machine, an external hard drive or an inexpensive flash-drive.
To Err is Human
People make mistakes. This is why we have pencil erasers and procedures to follow when handling data. Begin with naming conventions. If you name something “accounting” or “collections,” then it is possible to mix these up with similarly named files. Consider, for example, the problem posed by e-mail attachments — not malware, which is another issue, but attachment names. By saving an e-mail attachment with a name similar to your data file, and you not paying attention, you could easily overwrite your existing file with the e-mail attachment. Give your files a unique and, hopefully, informative name such as “ABCJanuaryCollections.”
Another, far more common, way users lose data takes place when the user editing a document or a spreadsheet accidentally deletes portions. This is another case where it is imperative that the user pays attention to detail because once the file is saved, the portions that have been changed are locked in and those sections that were deleted are lost.
The good news is that many applications have features that will store changes for you. These are considered advanced features and you will need to learn how to use them, but once you do, your work will be much safer. However, if you don’t wish to deal with all that, simply save your file under a different name before you begin to work, then make your changes to the new copy. Just remember, this is a working copy. Once you are done with it, make a very careful study of it before you rename it to replace the original. If you don’t, you could be making the same mistake that led you to work on an alternate copy in the first place.
The Recovery Begins
Happily, there is hope for lost data. There are a number of ways to handle data lost to physical damage as well as logical failure. It is also possible to recover files that have simply been “erased,” but not those that have actually been overwritten.
Physical damage — mechanical malfunction or damage to the disk itself — cannot usually be repaired by the end user, since opening the hard drive, for example, would expose the interior to dust and other environmental factors that would then make further crashes inevitable. Sometimes, the damaged mechanism can be repaired or replaced, allowing the disk to work; at least to the degree you can transfer your data to a more reliable medium. If this cannot be done, a specialized image is taken of the damaged disk, every readable bit being analyzed in the process, and transferred to a stable medium. Once there, an assessment is made for logical damage and the actual data recovery can begin.
Logical damage — where the data structure of the disk is incomplete or corrupted — is very common in data loss events and it must be corrected before any meaningful information can be extracted from the disk. The two most common tools to deal with logical damage are consistency checking and data carving.
Consistency checking is the process of scanning the logical structure of the disk to make sure that it is consistent with its file system specifications. In other words, the computer knows what ought to be there, does the disk measure up? This is not without its problems. For example, during the process of consistency checking, the repair software could easily erase data that it finds out of place on the disk, exacerbating the problem. However, if it works, you can read from it and write to it. If not, then you cannot and a reformatting may be in order, even though that would destroy all the data you are trying to recover.
Data carving is different in that it ignores file systems and extracts data by identifying the sectors and clusters that belong to the file being recovered. It does this by looking through raw sectors for specific file signatures. This capability comes at a price, however, since it can be very time and resource intensive. The user has to specify the block size of the data to be carved out once the signature is found and the sectors involved have to be sequential rather than scattered.
There is often confusion over whether something that has been deleted from a disk is really gone. The answer to that depends on whether the data has been overwritten. If it has, then there is no way to get it back. If not, if it has merely been deleted, then the data is still there.
The reason for this is that in many operating systems, deletion does not erase data. It erases the pointers in the file system that tell the computer that the data exists and where it can be found. Without those pointers, the data is as good as gone. Undeletion software can be used to recover the deleted files, but it is not foolproof. There is always the possibility that if the file is fragmented across the disk, all of the data associated with the file in question will not be found. The file also needs to appear in the directory and the sectors where the file was stored must not have been overwritten.
Recovering lost data is often difficult and the results are seldom if ever one hundred percent. The best way to solve the data loss problem is to prevent data loss in the first place. Keep you hardware up to scratch, with the latest controllers and drivers; make sure your operating system, firewall and malware protection are all fully updated, store your files away from your boot disk and make sure you make backups. It is not difficult to protect yourself and it is well worth the effort. —Charles Cooper
