on a Rotating Magnetic drive, block numbers are fixed, and an erase process that takes a few minutes:
• re-writes the first roughly 1,000 blocks where the directory was and the new directory will go.
• puts all the rest of the block numbers on the FreeList
• does not overwrite the rest of the data blocks on the drive.
This means that you can indeed apply aftermarket tools to 'rescue' some of the data blocks, and turn them back into files. But the filenames are not often recoverable. you may have a pile of thousands of files without any names at all. The folder structure is gone. Some files will never be recoverable. Every WRITE you make to the drive takes blocks off the FreeList to do so, increasing the likelihood that you will re-write an important block of a file you wanted. Be sure to copy rescued files OFF the drive to a different drive at least as large.
If you 'get away with this', and get some of the files you wanted, you are an amazingly lucky guy. Next time, you may not be so lucky. Think long and hard about how to make a backup copy of EVERY file you want to see again. More Drives are CHEAP by historical standards.
If this were an SSD drive, your files are unrecoverable and GONE in a few seconds.
