[[!comment format=mdwn
 username="Marco"
 subject="A possible solution"
 date="2015-05-19T11:03:22Z"
 content="""
While searching for the problem I found this:

http://feeding.cloud.geek.nz/posts/error-while-running-git-gc/
> git reflog expire --all --stale-fix

I can't verify this because I nuked the broken repository after recreating it.
"""]]