The details are not here for a cure but I see no mention of pest control. I don't allow IE use here since it created too much work to scan and eject spyware.
Run WINSOCKFIXXP. Then scan with Free AVG AntiSpwyare.
Maybe you'll find some pest.
In closing, no mention of internet connections so I'll see if you'll tell more.
Searching through this forum, I have found a few cases that are similar in some respects to my problem but they mostly concern specific routers or websites. Here's my problem...
My home network consists of 2 PCs, each running Windows XP Home Edition (SP2) with IE7 as the web browser on both. They connect together via a router which in turn connects to the Web via a broadband connection.
Up until 2 days ago, all was running perfectly on both PCs then one of my (adult) sons called in and asked if he could use his mother's PC (PC#2) to browse some car ads. About 40 minutes into his browsing, he suddenly found that EVERY Web page he called up drew a "Page Not Available" response from IE7 yet, sitting opposite him, using PC#1, I could readily access those same sites. Although IE7 was denying him access to the Web, he was still accessing his e-mail account that I've kept on that PC for him, while we were watching the screen, Norton Anti-virus successfully performed a Live Update and he was still able to access the printer, which is attached to PC#1, thus apparently ruling out bad wiring or router problems.
I first ran a complete system check with Norton AV, which found nothing nasty. I then tried rebooting that PC but that made no difference either. I tried re-installing IE7 but with similar lack of success.
Then I had a flash of inspiration (possibly an unfortunate choice of words there, as will become evident) - I had a recent Magazine Cover DVD that had Firefox on it, so I installed that. Bingo! Firefox enabled my son to continue surfing his car ads.
30 minutes later ... "Page Not Available" appeared again on every site he tried to access. Exit disgruntled son to his own Web-free home.
I uninstalled Firefox then reinstalled - no help. I uninstalled Firefox again then used a system restore point from a few days earlier then re-installed Firefox but still no change (nor with IE7 after the system restore, either). I searched for .EXE files saved that day. There were a few associated with the initial installation of Firefox, time-stamped before the successful use of Firefox but there was also a couple of files added in the Firefox Plugins folder relating to AdobeFlash, time-stamped very close to the first Firefox failure. Knowing that many car manufacturers use video loops in their Web sites, I presume that on two separate occasions my son had opened a site that required the Flash plugin to be downloaded and activated. There was no similar entry in the IE7 folders so it may have been the activation itself, rather than the downloading, that triggered the Web block. But then, it could easily have been something else on that site that caused the problem, the Flash plug-in merely being an innocent element.
Whatever the cause, I need to find a cure. The lack of Web browsing on PC#2 does have the advantage of keeping disgruntled son away but his mother needs Web access to her school administration site, so I need help restoring it on her PC or face losing my own PC to my wife! As the problem applies equally to IE7 and Firefox, it strikes me as not being a question as to which one is better than the other. So, does anyone have any ideas worth pursuing?