Getting that error?
Short answer: you fucked up, then Capistrano fucked up right behind you.
SSH into your deploy target, go into shared, and then frag the shared_cache directory.
Then, cap deploy:cold.
It normally happens when you try to set your repository as a local filesystem path. Capistrano populates shared_cache with an empty Git repo, and then tries to pull in your repository, which it can't reach... but it doesn't frag shared_cache, so the next time Capistrano looks, it's there, and goes, "Hey, we've already built the repository cache, let's just call git fetch and update it!"