Error -1 what does it mean?

Hi,
I have tried to export a master file from fcpx 10.08 but I get this error message: The operation could not be completed because an error occurred when creating frame 9351 (error -1).

I found the clip (a still) containing that frame and deleted it, tried to export again – with the same error message, frame number and all exactly the same!

I tried to export to other formats – same result. I tried to copy the whole video to a new timeline (ProRes 422) because all video was filmed by a Samsung phone, but I still got the same result.

Can anybody give a hint here? And where can I find a list of all error codes and their meaning?
Regards, Bjorn, Sweden

Error -1 can often be caused by corrupt render files, so try trashing them and exporting again.

We've built up an error message database that is available in our Crash Analyzer and EditCodes tools. You can find a list of currently supported error messages here:
[www.digitalrebellion.com]

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Thanks I will try trashing.
Bjorn

BUT it didn't work. The export was interrupted at exactly the same frame as before. I don't like to give up, but perhaps now is the time for that?
Regards, Björn