Errors during file transfer and burn

I'm trying to rescue files off a laptop that ended up with a corrupt windows xp boot file. I can browse the file I want in Knoppix just fine, but when I try and transfer more then a few at a time to the external drive, or after the 3rd or 4th file transfer if I am doing small groups I get this error:
The process for the file protocol died unexpectedly.

I can't manage to burn to DVD either, because when I do it gives me this error instead:
Fatal error during recording: Object is remote.

Any advice for how to get around these problems?