Firefox: XPCOM:Eventreciever freezes when downloading

[Laogeodritt]

Whenever I download anything other than a webpage (.html, .shtml, .php, etc.), its content, or text files, it freezes midway through the download. I can still use Firefox (the program itself does not hang) and do not need to end process by Task Manager. However, if I close all Firefox windows, the process firefox.exe still remains. I close it through Task Manager.

If I try to use Firefox or Internet Explorer anytime after the download freezes (and I cancel it), the browsers can't find the website. About half the time, the IM programs can't connect, and the other half of the time, they continue working normally.

Restarting does the trick, but as the computer shuts down (doesn't happen with log off), I need to manually end task for XPCOM:Eventreciever (or something to that effect).

Is there any way to fix this?

Here is some information pertaining to this problem:

OS: Windows XP Home SP1 (won't upgrade to SP2 since I use some programs which, I've heard, cannot work with SP2)
McAfee Internet security suite
Usually have MSN messenger (not Windows Messenger) and AIM active
I am using Firefox 1.0

Also, I've found out today that it'll do that when downloading with IE sometimes too, and then I can't access the internet at all. A few hours before I post this, the IM programs couldn't reconnect to their services either.I was trying to download a fan-made .mp3 music file on http://www.rpgamer.com when this happened.

Here are some programs that were active during this last happening:

FreeRAM XP Pro 1.4
McAfee Internet Security Suite
MSN Messenger
AIM
Some HP printer drivers
Teatimer.exe (it's the IE Resident from Spybot Search & Destroy and the registry guarding thingy)
Firefox.exe
Thunderbird.exe
calc.exe
Microsoft Office Word
notepad.exe

Please help!

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Also, I was wondering if there was some way of closing and restarting XPCOM:eventreciever without restarting the computer, since needing to restart is annoying and time-consuming (a bit too much stuff at startup trying to start all once, I think). Ending the Process firefox.exe and thunderbird.exe remenants after closing the programs rarely help with this situation, so I'm nearly always forced to restart.

Thanks in advance for any help you can provide.

Laogeodritt

NOTE: I just scanned with Spybot S&D and Ad-Aware SE this morning, and with my anti-virus last week, but it still happened then whenever I downloaded something.

 

[Laogeodritt]

Anyone? Please?

Someone suggested that I do a fresh install of Firefox. Would that help?

I had just upgraded from 1.0 PR to 1.0, by clicking that arrow in the corner that appears whenever updates are available, but I had this problem ever since I first installed and used Firefox, which was 1.0 PR. With IE before I installed Firefox, downloads did occasionally freeze (extremely rarely, I estimate around 5% of the time), but I could just cancel the download and I would still be able to access the internet. With this problem, described in my above post, I can't access the internet and I need to restart.