Checking USB flash drives and flash memory cards for correct functionality


Because the tested disk is completely filled by the F3 write test as described previously, you need to delete the existing files to use the medium for your own data again. This step can easily be done in a file manager.


In overwriting the entire storage medium, F3 performs another useful task in passing  – secure deletion of old files. Existing sets of old data can no longer be reconstructed after write testing the medium with F3. The 1GB files that F3 creates are filled with meaningless strings. Although you can recover them with forensic tools such as PhotoRec, you cannot access the user data originally stored on the disk. Therefore, F3 can also be used to get rid of sensitive personal data on flash memory cards or USB sticks that you want to sell, for example.


F3 is a tool that should be in place on the computer of any user who cares about the integrity of their flash memory media. This small command-line program not only tests various flash memory devices reliably but, when used properly, also overwrites existing legacy data, giving users a dependable way to prevent their data from being restored. The software takes up very little space on your hard drive, and its use is self-explanatory; even users who are not familiar with the technology of flash media will be able to cope with the application.

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