I have this problem and it usually requires rebooting the machine. I can uninstall Flash 7 but this is the only version that I seem to be able to get access to and there seems no way to get around the problem.
I have seen advice that installing IE 5.5 will do the job but where can I get an IE5.5 installation from?
The problem does not occur with Mozilla.
How old is this problem? Is Microsoft aware of it? Is Macromedia? How does one advise them?
Brenton