Which version of IE?  Is it one particular site, or all sites? Most problems with IE are caused by spwyare, malware or other internet parasites.  Have you scanned your computer with at least two different antispyware programs?  Are you running any software that would help to prevent spyware/malware infections?

Steve

It would help if the entire message is shown. Microsoft has downloads to fix specific problems which causes IE 6 to close. I had a problem after installing security update 942615 on my PC which is running Windows XP Service Pack 2. If your notice includes the module name ulmon.dll, the specific fix for that was issued by Microsoft on 12/27/2007. That download number is 946627. However, other fixes exist for other modules. Does a module name show up in your exception notice?