checked out files prevent submitting

System

Hey,

when I try to submit some files to my workflow, I manage to get all the way till the submit task. Once the workflow gets to the submit task, I get a conflict saying "Checked out files prevent submitting".
I am not quite sure why this comes up, since any file I try to submit is not locked or has been edited.
When I try to do "resolve conflict", the screen which comes up says that there is actually no conflict with any of the files I try to deploy. I tried all the options the "resolve conflict" screen gives, including overwrite, and retry, but nothing works. I am a little confused as to why this happens.
Any help would be appreciated.

Thanks,
Ido