how to troubleshoot flash player on Internet Explorer 8?

"What I know is that sometimes when you upgrade flash player the old plugin is not removed. IE believes that you have the new version and will report that with JavaScript but the old version is still the one that gets loaded.

Here is a website where you can test

http://millionmind.com/ie8_faulty_flash_player_installation"

"From some threads in the wild like this one, it appears this behaviour is not limited to 64bit machines, Vista or Win7. It is probably a security settings issue, and turning off IE8 Protected Mode (Tools > Internet Options > Security > [ ] Enable Protected Mode) allows flash to work, for me. Not sure what the ramifications are for this, probably not good so it's definately only an interim measure.

On the thread mentioned David Spector says

... it's a security bug. One can argue
whether it is Microsoft's fault or
Adobe's fault,... Microsoft changed the way that
certain packages are signed with
security certificates. Adobe didn't
get the word, and continued to sign
their releases in the same old way.
The result is that current Internet
Explorer browsers, versions 7 and 8,
report an error for any website
running Flash, and refuse to download
the latest version.

David goes on to conclude the changing security settings don't work, but that is not true in my case at least (perhaps he changed security level but not proteced mode?).

The problems reported with Firefox is an unrelated profile or extension issue. Portable Firefox on the same machine has no problems with flash."