Yeah I tried to install ubuntu on my computer and instead it wiped my USB drive (which has critical files) and now there's ubuntu 'installed' on my USB drive.
How do I get my files back?!?!
Data recovery tools e.g. Testdisk can recover data from any medium including an USB stick.
The included tool Photorec will recover remnants of individual files but file names and directories will have to be restored manually.
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