git: cannot lock ref

Quick fix

Read the commands before running them. Anything that restarts a service, deletes data or changes permissions should be tried on a non-production system first.

ls -la .git/refs/heads/*.lock .git/index.lock 2>/dev/null
pgrep -a git
rm -f .git/refs/heads/main.lock .git/index.lock
git pack-refs --all
git gc --prune=now

How to diagnose Git errors

Git errors are frightening mostly because the messages describe internal state rather than what to do. The reassuring fact is that almost nothing is lost: git reflog records every position HEAD has held, so a bad rebase, a hard reset or a deleted branch is nearly always recoverable. Before running any destructive command, note the current commit hash.

If the quick fix above does not resolve it, work through these steps. They apply to this whole class of error, not just to this one message, which is usually what saves the time.

1. Run git status and read it fully. It tells you the current state and usually names the exact command to move forward or abort.
2. Use git reflog to find any commit you think you have lost, then git reset --hard <hash> or git branch recovery <hash> to get it back.
3. For a rejected push, run git fetch then git log --oneline HEAD..@{u} to see exactly what is on the remote that you do not have. Prefer --force-with-lease over --force, which refuses to overwrite work you have not seen.
4. Abort rather than improvise when a merge or rebase goes wrong: git merge --abort, git rebase --abort, git cherry-pick --abort.
5. For repository corruption, run git fsck --full. If objects are missing, re-cloning and cherry-picking your local work is usually faster and safer than repairing in place.

Tools worth reaching for

• git status
• git reflog
• git fsck --full
• git log --graph --oneline --all
• git diff --check

Authoritative references

Primary documentation for this error, worth reading before applying any fix in production.

📖 git-scm.com

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Something missing or wrong?

This entry is maintained by hand. If the fix is out of date, incomplete, or you have a better one, email a correction and it will be reviewed.