Once the R4 is plugged in to the computer, find it in 'my computer' and right click on it. Choose format, and it will erase every file on the R4, corrupted or not. That's how you get rid of files you can't delete.
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Format it.
Once the R4 is plugged in to the computer, find it in 'my computer' and right click on it. Choose format, and it will erase every file on the R4, corrupted or not. That's how you get rid of files you can't delete.