First off, if a video is corrupt after data recovery then there is no tool to "repair" the videos. 99% of the time it's because the files contain the wrong data, and you can't "repair" that. You would need proper data recovery of the correct sectors.
A few questions so I can point you in the right direction. How full was the drive? If if was ever, at any point in history, full or near full, then the files are most likely fragmented and recovery will be extremely difficult.
Also, what type of files are they? AVI, FLV, MP4, etc.
Also, did you recover the data back onto the same drive your were recovering off of, or onto a different drive?
Is it actually a spinning disk hard drive, or an SSD, CF card, SD cart, etc.?
A couple nights ago I accidentally reformatted my external HD while trying to install windows via bootcamp on my mac. I bought a data recovery tool to get back all the files I lost and it seems like I recovered them but the video files (the part I most need) are all corrupt/broken. I tried using a free repair tool as well as VLC's built in repair tool but neither seemed to work. Any tips?
Thanks!

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