i can't finalizing my movie project: error 49, what is this?

Hi

Error -49opWrErr File already open with write permission

Trash the preference files while application is NOT Running.

from Karsten Schlüter

Some users notice on exporting larger projects from within iMovie that this operation is aborted with an 'error -49'

This issue occours only on MacOs machines using 10.7x

try switching-off the Local Mobile Backup

in Terminal copy/paste

sudo tmutil disablelocal

Re-launch Mac

Yours Bengt W