Corrupt file systems and partitions
Data on a hard drive can be unreadable due to damage to the file system or partition table. In the majority of these cases, at least a portion of the original data can be recovered by repairing the file system or the damaged partition table using specialized data recovery software. In some cases data can be recovered using relatively simple methods and tools; more serious cases can require expert intervention, particularly if parts of files are irrecoverable.
Resulting from crashed heads and/or platter damage within the hard drive. This form of data recovery gets more expensive as it requires a clean lab environment to disassemble the damaged hard drive. Once repaired (temporary) the data can then be recovered to a new media source. This is known as a physical and a logical data recovery. Think of your car. The main computer crashes (physical) and is replaced with a new one, but still requires a flash of the software (logical) before the car will run as designed. If there is damage to the platters there is a method to recover the data called “File Carving”. This will be discussed at another time.
There is no practical method for recovering data that has been overwritten.
Now if your hard drive is a Solid-State drive (SSD) recovering overwritten data is possible as these hard drives use flash memory to store data in pages and blocks.
Our next Data Buzz will discuss metadata, data about data, which will provide a bit more insight into how the structure of data can be recovered.
Until next time from Data Buzz.