Please describe the problem:
I'm trying to render the same project twice and this failes.

Steps to reproduce:
1. Create a project with some clipse
2. Render the project
3. Wait until finished ( Don't close the render project dialog)
4. change the filename of the export ( I think not relevant)
5. Press the record button again


Actual results:
Fails to render for the second time

Expected results:
Render again to a different file

Does this happen every time?
yes

Other information: