Periodically Firefox will close and then restart. I've been unable to identify a reason for this. Neither Chrome or IE has ever closed on their on.

Anyone know of a reason for this?

Sounds like a simple crash to me.
What have you been doing when this happens ?

Reading news, internet searches, Firefox is open in the background while I'm using another program (no consistency as to which one.) I've yet to identify a connection between my actions and Firefox closing.

When you say it happens, how often, maybe once a week ? Or a couple times a month.
My son and I both use it also, and we have it happen, about twice a month. Normally when I am doing "a lot" on it.

Firefox updates itself with intermittent small added on fixes, something may have screwed up. Download the latest full install then uninstall the present and reinstall new. I always make note of what addons and extensions I'm using prior to uninstalling and go get them right after installation. If you don't do too much with configuration settings you can remove the Mozilla folder as well after uninstalling to reset everything. Sometimes uninstalling doesn't take everything in the directory with it. If offered a clean install take it.

Hi!

I use Firefox a lot, and I have this issue. What I know is that Firefox is a 32bit program, so far as I know they haven't release a 64bit windows client, but this means that Firefox can only address or allocate up to 4gb of ram. It usually gets to about 60% of that and then crashes. Firefox, and some of it's popular addons like adblock, have severe memory problems, or memory leaks. So when a you open and close a page your system will have a bunch of allocate and unreachable ram. When it gets to a certain level it will crash. It happens to me about every three or four days. Chrome doesn't do it for me. I don't use IE because... well it's IE.

I hate to say that it's normal operating procedure for Firefox, but it kind of is.