I had my firefox on my old computer and It crashed all the time, about every 15min or so. I thought it was the computer. So when we got our new computer i installed firefox. When we first got it it NEVER crashed. The sec. day we updated out McAfee and our site adviser and it started to crash again. Do you have any fixes for this? Our Firefox is up to date. Our McAfee is up to date. we can't possibly get rid of out Virus or family protection.
Create a new profile as a test to check if your current profile is causing the problems.
See "Basic Troubleshooting: Make a new profile":
There may be extensions and plugins installed by default in a new profile, so check that in "Tools > Add-ons > Extensions & Plugins" in case there are still problems.
If that new profile works then you can transfer some files from the old profile to that new profile, but be careful not to copy corrupted files.
If you have submitted Breakpad crash reports then post the IDs of one or more Breakpad crash reports (bp-xxxxxxxx-xxxxxxxxx-xxxx-xxxxxxxxxxxx). You can find the IDs of the submitted crash reports on the about:crashes page. You can open the about:crashes page via the location bar, like you open a website.
Have a read of Firefox crashes - Troubleshoot, prevent and get help fixing crashes. Please try to obtain and forward crash IDs (paste them into your next reply).
This forum is not the correct place to have discussions about the pros and cons of any particular software, but maybe an exception is where software may be detrimental to Firefox.
Maybe consider whether McAfee is he best solution to security problems, and especially if you do use it, why use McAfee site advisor. Some of the developers working on firefox seem rather concerned about the side effects of specifically Site Advisor. (http://blog.mozilla.com/nnethercote/2012/02/17/the-mcafee-site-advisor-add-on-has-an-appalling-memory-leak/ &http://blog.mozilla.com/nnethercote/2012/02/16/mcafee-is-killing-us/ )
If a computer has a specification allowing Windows 7 to run, it is unlikely to have problems running Firefox.