You have a branch named <branchname> you do your operation that fouls up your branch. If you check with git log --reflog --all you will see with this magical

You have a branch named <branchname> you do your operation that fouls up your branch. If you check with git log --reflog --all you will see with this magical command that git DOESN'T REMOVE any commit. Your old tree is still there, only normally hidden. The commit that was there before you fouled up your branch is still there. You now only need to set your branch to the old commit. A branch is nothing else than a pointer in the tree. You have 2 possiblities to change the commit a branch points to 1. git branch --force <branchname> SHA1 (works only if <branchname> is not the current checked-out branch. Simply checking out with the SHA1 works also as it deteches the HEAD). 2. replace the SHA1 in the text file in .git/refs/heads/<branchname> by the SHA1 where you want the branch to point to. With that, your repo is in the same state it was before your error.