I had this issue today on a repo.
It wasn't the +refs/heads/*:refs/remotes/origin/*
issue as per top solution.
Symptom was simply that git fetch origin
or git fetch
just didn't appear to do anything, although there were remote branches to fetch.
After trying lots of things, I removed the origin remote, and recreated it. That seems to have fixed it. Don't know why.
remove with:
git remote rm origin
and recreate with:
git remote add origin <git uri>