Dave wrote:

<<Neither IE (reloaded with the OS, which means it's not up to date) nor 
Firefox (11.0, downloaded about 2 weeks ago) can ever connect to a web page>>

1. You didn't mention firewall settings--have you checked these, or tried 
disabling the firewall temporarily?

2. Try turning both the W7 and a-v updates off---just maybe one of these is 
taking priority while searching for its server, and causing any other 
traffic to timeout (which will result in that IE message). Unlikely, but 
not beyond the realms of possibility.

3.  Much more likely---you mention that you only "restored" the OS 
partition. Did you reformat first?  And does this imply that there are 
other partitions or drives in the system which you have not 
reformatted?  If so, the following comments may be relevant.

Not long ago, I inserted my USB flash drive into a computer which 
subsequently turned out to be badly infected by viruses and malware. At 
that point, nothing appeared to happen.

But when I later inserted that flash drive into my own computer, Avira 
instantly went absolutely berserk, screaming out that every .exe file on 
that flash drive was infected by a certain virus. There is a certain class 
of viruses which can invisibly jump from one partition or any other drive 
in the system onto any other partition or drive.

Unless you have reformatted ALL other partitions/drives in your system, is 
it possible that this could have happened, and that there are remnants of 
the original virus either remaining in your OS partition or which might 
have leapt across from other partitions/drives?  This could conceivably 
have the effect of blocking your internet access and/or preventing security 
updates. If it's a recent virus, your a-v would probably not detect it 
until its updates have been installed. I wouldn't have any faith in any a-v 
software which let that virus in in the first place.

Hopefully you will find a simpler solution to your problem, and it may well 
be simply a W7 setting somewhere applicable to your modem. But the fact 
that updates appear to be blocked makes me very suspicious of some sort of 
malware activity.

Don Penlington

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