You may have left out a detail. This is a common complaint of Netscape, Mozilla and other users.
Even more common are the number of pests that install themselves and since they need an internet connection, the autodisconnect will fail.
Consider being pest and parasite free (these are not virus.)
http://reviews.cnet.com/5208-6132-0.html?forumID=32&threadID=1313&start=0 has the five tools and scans for such things.
Be aware the new bugs are not always detected with your installed antivirus because it installed itself and is now able to dynamically defend against your scans.
If this was my machine, I'd do all five scans, to be sure. You can find CWSHREDDER at http://www.spywareinfo.com/~merijn/cwschronicles.html
Windows XP Home Edition, P4 1.5mhz, 512mb ram, IE6
For some reason, the dialogue box which asked whether I wished to disconnect or stay connected (when I closed IE6 at the end of a session) does not appear any more.
The appropriate box (internet options/connections/ISP settings/dial-up advanced/disconnect when connection may no longer be needed) is still ticked but the dialogue box no longer appears when I close IE6.
Have installed all updates available and have run sfc/ scannow to no avail. Any clues as to what may have caused this would be most appreciated.

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