....change the file's name, adjust it's properties, or change the file extension? Have you tried to copy to another folder on the computer, or only to the flashdrive?
I made a recording on a voice recorder and I listened to it using Windows Media Player. When I tried putting it on a flashdrive, it said the file was corrupted and couldn't be moved. It was a 34 minute file, but now when I try to play it, it's less than a second. When I look at the file properties and details, it still says the file is 34 minutes, but it is not the case when I try to open it in Audacity or VLC player. I'm not sure what to do, how it happened, or how to fix it.

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