This was a bit of a weird problem: I kept getting in Event Viewer error 20035 for “Rasman” and 7023 for “Service Control Manager”.  This manifested itself, amog other things, in the impossibility to access some internet pages (even the windows update page). 

Solution:

After a thorough google-ing for information I found the following solution:

Delete in the registry the NextID value HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Telephony\Cards\NextID