Restore My Files - How Data Recovery Programs Work

How Data Recovery Programs Work

Power outages, natural disasters, computer freezes, viruses or simple human errors can all be the cause of one of today’s most common technical “plagues”: data loss. It’s estimated that millions of users suffer from data loss issues worldwide each year and millions of dollars are lost due to the fact that important documents get deleted. Fortunately for us, data recovery programs become more and more proficient with each passing year and it’s safe to say that unless the data loss occurred due to some extraordinarily severe events such as hard disk burnout, extreme magnetization and so forth, your data can be recovered. It’s just a matter of having the right tools and the right data recovery program(s). But in order to understand how a data recovery program can help us get our stuff back, we first need to take a look at what happens inside our hard disk when a file gets deleted or “lost”.

Delete a useless file in Windows explorer by using the “Delete” button on your keyboard or right clicking on it and choosing “Delete”. If your operating system is set to send deleted files to the recycle bin, your deleted file will be stored there. However, if you have set Windows to skip sending files to the Recycle bin and instead delete them from memory, the file is completely gone right? Wrong! What is gone is your visible link to that file. Consider your hard drive a website with a link on its homepage to the page “content.html”. When you delete the link on your homepage, you won’t be able to see “content.html” anymore, but that doesn’t mean it’s gone from the server. It’s still there; you just can’t see it from the interface provided by the website.

Another analogy can be made to a book. Each file is a unique page and when you delete a file, it won’t mean that the page it represents gets torn from the book and thrown away. Instead, that page will simply stop showing up in the Table of Contents.

What a data recovery program does is trace back and try to restore the original “Table of Contents” of your hard disk’s file structure in order to find those lost pages. The longer the file structure changes, the harder it will be to recover the lost data and after a while, it will be impossible even for the most complex data recovery programs to get back 100% of your lost files. This is due to the fact that your operating system keeps deleted files in a reserved space which has limited memory capacity. When this space fills up, your system will start overwriting those older lost files with newer lost files. Therefore, a file you accidentally deleted yesterday is far easier to recover than a file deleted 5 months ago. Additionally, it will be harder to recover 100% of the older file, because the operating system may have overwritten only specific parts from it, leaving the rest intact.

Of course, each data recovery program works in its own way and has its own methods of accessing those lost files and rebuilding the initial file structure. However, all of them are based on these fundamental principles and understanding these is the most important step in achieving full and efficient data recovery.

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