I've got TortoiseBazaar installed on my Windows laptop, and I was trying to branch a repository hosted on my VPS to another directory on my VPS, and I got this lovely error: bzr: ERROR: Unknown branch format: 'Bazaar Branch Format 7 (needs bzr 1.6) That lead me to this mailing-list archive: http://osdir.com/ml/bazaar/... Then I tried following the instructions here to add the Launchpad PPA to /etc/apt/sources.list, but they forgot to mention that you need to do this: sudo apt-key ......