If my system has not changed then IT must be YouTube that is a fault.

I have the same problem as other people do. Last night youtube worked fine and since then I have not changed anything on my system. I have the lastest flash player and JavaScript is switched but this morning I cannot watch any YouTube vids. Other vid sites work fine. I suspect YouTube has changed something. The YouTube HELP service is SH*T thus there is no one you can contact to explain the situation.

I have tried uninstalling flash then installing the lastest flash and this still does not work.

By 'cannot watch', do you mean they just don't load, or you get some sort of error?