To clarify, the problem happens when my computer wakes up from sleep - at that point the network adapter needs to be reset. I tried uninstalling McAfee 2010 and the problen went away. I have reinstalled, and have the problem again.
I appear to be having this SAME problem. (Windows Vista)
Ever since the most recent McAfee update, whenever my desktop resumes from "SLEEP", I have absolutely no connectivity to the network... no networked printer and (obviously) no internet. To correct the problem I have been initiating a reboot. I do not reset my router as I have a house full of people and "toys" that could be using the internet at any time.
Any help would be greatly appreciated!
My problem is solved! First I tried to update the Network Adapters NVIDIA nForce 10/100 Mbps ethernet driver in Device Manager, and got the message that Windows says I have already got the latest driver (184.108.40.206 of 8/1/08). Then I looked on my computer manufacturer's website (emachines) for an updated ethernet driver and found one that seemed to have a later date but an earlier version number (67.8.0 of 9/9/09). I did internet chat with the emachines people and they could not answer my question about whether it was a newer driver or not. Actually they did not seem to even understand the question. So I downloaded it and installed it and after checking Device manager again it showed up as 220.127.116.11 of 3/25/08 - so it was an older driver - but it solved the problem!! I have not noticed any new problems.
It would be nice though if McAfee fixed Internet Security 2010 so that it did not do this anymore. Any comments from McAfee people?
Have you tried resetting the network adapter as a quicker method than a reboot? I right click on my internet icon which is at the bottom right, choose Diagnose and Repair, and then choose Reset the Network adapter. And hope my driver info is helpful.