I tried to remove a file from my remote repo by running:
git filter-branch --index-filter 'git rm --cached --ignore-unmatch Rakefile' HEAD
But Git complains that
Cannot create new backup. A previous backup already exists in refs/original/
Force overwriting the backup with -f
rm: cannot remove /.git-rewrite/backup-refs : Permission denied
rm: cannot remove directory /.git-rewrite : Directory not empty
This was after I already deleted the .git-rewrite directory on Windows.
How can I remove that file? It's a 29Mb file sitting on my repo, so I quite need to remove the file.
I tried to delete the commit in git rebase -i, but apparently because the commit touched a lot of different files, Git complains of conflicts and I aborted to be safe.
You have already performed a filter-branch operation. After filter-branch, Git keeps refs to the old commits around, in case something goes wrong.
You can find those in .git/refs/original/…. Either delete that directory and all files within, or use the -f flag to force Git to delete the old references.
git filter-branch -f \
--index-filter 'git rm --cached --ignore-unmatch Rakefile' HEAD
Use this command to remove original backup:
git update-ref -d refs/original/refs/heads/master
Here is gist I used to filter-branch my git repo: https://gist.github.com/k06a/25a0214c98bc19fd6817
I had the same problem and the answer above didn't fix it. There was no .git/refs/original/ directory left. The solution for me was to delete the .git/packed-refs file.
Add a force to the filter branch command.
来源：https://stackoverflow.com/questions/6403601/purging-file-from-git-repo-failed-unable-to-create-new-backup