title: tortoisehg hangs on update after using rebase + strip on multiple branches
body: <p>First things first, I'm a total moron for even being in this position at all. Newish dev with &lt; 2 years experience and not a lot of time with version control, much less hg and tortoisehg.</p>
  
  <p>I wanted to revert a merge, so after several failed attempts to create a new branch from my last good commit and merge it back into my local branch, I discovered the rebase extension could strip back to a good commit. (That said, since I had already pushed my bad commit, it didn't really solve my problems).</p>
  
  <p>I went ahead used rebase > strip a few times nevertheless, and now tortoisehg hangs whenever I try to update. </p>
  
  <p>hg cli still works, it's just tortoisehg that I seem to have broken. Tried uninstall/reinstall of tortoise, no luck.</p>
  
  <p>I find that other guys in the office can pull and update without problems, so it's strictly a local problem.</p>
  
  <p>Any suggestions on how to restore functionality? Thanks in advance.</p>