$ git checkout 7716421c4bb9f0594fc6ecfb56a1f31179f9a6b0 fatal: reference is not a tree: 7716421c4bb9f0594fc6ecfb56a1f31179f9a6b0 $ git fetch <somewhere> 7716421c4bb9f0594fc6ecfb56a1f31179f9a6b0 ... $ git checkout 7716421c4bb9f0594fc6ecfb56a1f31179f9a6b0 Previous HEAD position was 0fce85d... Avoid bash-ism HEAD is now at 7716421... lockfile: remove unable_to_lock_error