You can find on internet many file (or more generally used term data) recovery or storage medium recovery tools and articles about how to do it.
But I was neither successful in searching for post recovery process tools and nor for any useful articles about it.
Let’s look why file and storage media recovery tools are needed:
1) mistakenly deleted files by user
2) mistakenly quick formatted storage media by user
3) corruption of storage media’s file system master file records section - there are many root causes:
- operating system crashes
- operating system BUGs
- viruses and trojans
- power supply interruptions
- non-safely stopped operation and non-safely removed storage media
- radiation (X-ray, strong electro-magnetic waves)
4) physical media corruption - very breadth area of reasons, but most of them are:
- partial physical destruction (like HDD fall from table)
- regular product end of life (yes, all storage medias have limited lifetime, but that’s not an interesting attribute for many users)
I hear your question what the hell is phrase “storage media”? Simply, that’s all the devices you can store your files on:
1) FDDs = floppy diskettes (earlier born readers will remember)
2) HDDs = hard drives (today massively used also as external USB hard drives, because of highest available storage capacity)
3) SSDs (USB flash disk as “hard drive”; smaller capacity but much more faster than HDDs)
4) USB flash disks (ideal for temporary file storage and transfers),
5) CDs, DVDs and other plastic cakes with hole in the center
6) CF, xD and other flash memory cards (based on same technology like USB flash disks; used mainly in mobile phones, tablets, cameras and other “smart “ and small portable devices)
Now briefly about file system and its master file records section. Every storage media needs to have some organizational rules how data are stored on it. Particular method how information are stored on media depends on used file system. Today there are quite many known file system types, mostly used are FAT32, NTFS, ext2, ext3. There is logical question why there are so many types? Well, every file system has its own pros and cons, and areas where it best fits in. Because of easiest organization rules, what simplifies implementation in portable devices, there is widely used FAT32. Second aspect is that for portable devices there are mainly supplied tools running on Windows operating system, for which it is native file system. But, finally, every particular file system has area where are stored information of file location with several base attributes (such as name, creation date and time).
The level of recovery success depends on many things. The first and core thing you have to do, when you consciously lose your file(s), is to prevent your storage media from next regular usage. Less time the media is ordinary used since data loss means higher probability of file recovery success.
For now, my aim is not to describe options for your data recovery. You can find many articles and specialized tools for recovery at internet.
So, you’ve done successfully complete or partial recovery. Is it really all done? Let me ask you one simple question:
Are you sure all your recovered files are not corrupt?
The answer is, and no matter on maturity of your recovery tools nor excellence of your techniques used, your files may be recovered only partially. Recovery tools are replacing unreadable or inaccessible parts of recovered files with zeros / nulls. Worst case is file completely filled with zeros. That’s not the only problem of recovery tools. File might be partially overwritten by another file or data, what is sometimes hard to detect. Same problem is with physically corrupted storage media, where recovery is trying repeatedly reading corrupt storage media area, and successful read does not mean every time correct data read.
It makes no sense to keep complete corrupt files (filled with zeros / nulls), because it’s waste of space.
Partially corrupt files are many times not usable at all, for example one compressed file in archive. Another situation is compressed archive with complete backup of your PC that contains huge amount of files. Such a partially recovered compressed archive may mean recovery of huge amount of “recovered” files. It really depends on situation, there is no sense to keep file with missing high value part (to better imagine, consider you have e-book with many unreadable pages - how much does such an e-book worth?).
Finally, keeping corrupt files is waste of your money:
1) money spent on your new storage media filled with unusable files
2) as Benjamin Franklin says “time is money”:
- time spent on individually checking of such a files
- time spent on organizing such a files
- time spent on browsing your media filled with many corrupt files
© 2013, Radoslav Kastiel