$ sudo add-apt-repository https://l...content-available-to-author-only...d.net/~tortoisehg-ppa
 
$ sudo apt-get update
[...]
W: Failed to fetch https://l...content-available-to-author-only...d.net/~tortoisehg-ppa/dists/precise/main/source/Sources  The requested URL returned error: 404
W: Failed to fetch https://l...content-available-to-author-only...d.net/~tortoisehg-ppa/dists/precise/main/binary-amd64/Packages  The requested URL returned error: 404
W: Failed to fetch https://l...content-available-to-author-only...d.net/~tortoisehg-ppa/dists/precise/main/binary-i386/Packages  The requested URL returned error: 404
E: Some index files failed to download. They have been ignored, or old ones used instead.
 

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