Git error on git pull (unable to update local ref)

I only have branch master and im getting this error every time i try to "git pull":

error: Couldn't set refs/remotes/origin/master
From /var/lib/git/xxx/project
 ! a0f80ea..49177a3  master     -> origin/master  (unable to update local ref)

and when i do "git pull origin master" i get:

error: Couldn't set ORIG_HEAD
fatal: Cannot update the ref 'ORIG_HEAD'.

i have been searching but cant find why

Solution 1:

My team and I ran into this error, unable to update local ref, when doing a pull in SourceTree.

Update 2020: Per @Edward Yang's answer below, @bryan's comment on this answer, and this question/answer you may need to run both git gc --prune=now and git remote prune origin. Running only the former has always worked for me but based on ppl's responses I think both are necessary to address different causes of the error.

We used:

git gc --prune=now

This removes any duplicate reference objects which should fix the issue.

Here are a few links where you can learn more about git references and pruning :

git tip of the week

git-prune documentation

git references

Solution 2:

I solved as below:

git remote prune origin

Solution 3:

with gitbach line commande, use git update-ref to update reference of your local branch:

$ git update-ref -d refs/remotes/origin/[locked branch name]

then pull using $ git pull

[locked branch name] is the name of the branch that the error is happening because of mismatch of commit Ids.

Solution 4:

Try to use this command in your git repository root folder:

rm .git/logs/refs/remotes/origin/master