Firefox already running when trying to start it the second time

[Oceanwatcher]

I am still on my friends PC and he has another small problem. He works around it, but would love to find a way to solve it.

If he closes Firefox on his PC, it looks like it closes. But when he try to open Firefox again, he gets a message that it is already running and to get around this, he has to open the System Monitor, find Firefox and kill it there (yes, i know this can be done from CLI :-) ). Then it is possible to start Firefox again...

He first got this problem in FF 3.0.x and then installed 3.5, but the problem remains.

When the problem started, he was using Kubuntu 9.04, now he is on Kubuntu 9.04, but upgraded KDE to 4.3 rc3. No difference. Just more stable and looking nicer :-) And a lot of other improvements!

[GilGib]

Re: Firefox already running when trying to start it the second time

I had this problem when I was using 9.04 rc and it went away after a few updates.
Others also had this problem and there are a few posts about it. I don't know what update fixed this.
Check out post by oblekt on 7-19-2009. Problems seems to be locks on Profile

[Chopstick]

Re: Firefox already running when trying to start it the second time

I'm using kubuntu 9.04 with KDE 4.2.4 and I also have this problem, on both my office PC and my laptop (same OS/DE). The problem appeared after I upgraded from 8.10 to 9.04.
kubuntu 8.10 = KDE 4.2 did not have that! And interestingly it does not always happen, and I can not see any systematic behavior so far...

[Telengard]

Re: Firefox already running when trying to start it the second time

Have you tried disabling add-ons?

Be sure to check the Firefox optimization and troubleshooting thread at Ubuntu Forums for other possible solutions.

[SCBrazil]

Re: Firefox already running when trying to start it the second time

One more to the list here.

I have no idea what causes it under the hood but I have tried different ways of provoking it.

I found that shutting all Firefox windows on all desktops before switching off the PC and allowing it to fully load when I start up - i.e. allow the music to roll and wait a few seconds - the problem does not occur.

[doctordruidphd]

Re: Firefox already running when trying to start it the second time

This seems to be a return to an old problem; it is happening in karmic as well.
Starting with a clean .mozilla, with no extensions, does not solve the problem.