I've just found out that someone committed some time ago some changes locally, that was revision #410, now the right version is #638... that created a branch in that person's mercurial history, and I want to get rid of it... I tried to execute an Undo > Backout... but it won't let me...
The error message I got is:
That person's Mercurial history:
What can I do to get rid of that branch? The changes that it was supposed to do were already made some revisions ago...