Could be malware's doings. To be on the safe side,
Please follow MicroBell's 5 Step process outlined here
After running through all the steps, best thing to do is have one of the HijackThis helpers take a look at a log.
Please download HijackThis - this program will help us determine if there are any spyware/malware on your computer. Double-click on the file you just downloaded.
Click on the "Unzip" button to install. It will by default install to the directory - C:\PROGRAM FILES\HIJACKTHIS\
Double click on HijackThis.exe to run the program.
1. If it gives you an intro screen, just choose 'Do a system scan and save a logfile'.
2. If you don't get the intro screen, just hit Scan and then click on Save log.
3. Post the hijackthis.log file in the HijackThis Log Help forum. Do not fix anything in HijackThis since they may be harmless.
I'm also facing same issue.IE&Mozilla browser closing automatically ....
IE Version:6and tried updating to IE 7..
Scanned and removed all virus......Updated with all microsoft patches...Still same issue
please find hijackthis.log below
Logfile of Trend Micro HijackThis v2.0.2
Scan saved at 11:56:11 PM, on 05/02/2009
Platform: Windows XP SP2 (WinNT 5.01.2600)
MSIE: Internet Explorer v7.00 (7.00.6000.16735)
Boot mode: Normal
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