I ran into this problem where I was unable to install Firebug in Firefox. It would act like it was installing, Firefox would restart, but the plugin was simply not there.
A little research revealed there could be a variety of reasons for this, but for me it turned out Avast! antivirus was preventing it from working.
I disabled the Network service in Avast! long enough to try again, and it all worked.
Hopefully this will help someone else who runs into the problem.






After eating lunch at a local restaurant yesterday, I noticed that when I was signing my receipt they had printed my whole credit card number on there. I hadn’t seen that happen in years, and I immediately scratched it out. I happened to be with a group of cyber security guys, and they were all in disbelief as well.
