The system is Win7 64 bit, fully updated. Anti-virus program is F-Secure, nothing detected. MalwareBytes also detects no problems. The problem is that some web sites do not display, including the the download site for IE9. Also, on Youtube
I can play some videos, but not others. One that will always fail is youtube.com/watch?v=LGzEVarZm8k. I get the circular indication that the film should be downloading, but then the message that an error haas occurred. I have tried the usual tricks of running IE without any add-ons, no change. I have also reinstalled the Flash player and Java, no change. MS has a diagnostic tool that will help detect problems with IE, but it came back clean. I have already deleted all temporary files and
cookies, as well as the Windows Prefetch directory. Also tried turning off the firewall, no luck.
What can I try next, other than the usual comments about FF and Chrome?