Solved by no protocol specified in VIM

On Debian wheezy, a new user, Walter, is added. When using vim, Walter exits when editing text:

No Protocol specified <br/> no protocol specified <br/>

This is because the added user has the permission to read the $ Xauthority file.

Wolf @ wheezy :~ $ LS-L $ Xauthority <br/>-RW ------- 1 wolf 51 February 24 15:19/var/run/gdm3/auth-for-wolf-3Bc4J9/database <br/> # Add this user (simply click all) read $ Xauthority <br/> wolf @ wheezy :~ $ Chmod + RW $ Xauthority <br/> wolf @ wheezy :~ $ LS-L $ Xauthority <br/>-RW-r -- 1 wolf 51 February 24 15:19/var/run/gdm3/auth-for-wolf-3Bc4J9/database <br/>

Run Vim again.