Comment 3 for bug 949932

I realise now that I had not actually closed the Software Sources dialog, though I thought I had, it was hidden behind another window. I was therefore trying to close the Update Manager whilst the Sources window was still open. I came back here to mark the bug as invalid but see that someone else has marked it as affecting them within minutes of me reporting it.
Unfortunately I killed update manager before realising, so I cannot absolutely confirm now that this is what happened.