"The requested look up key was not found in any activation context" WTF does it mean??T

[zookeeper]

Every time I try to open anything this message comes up! Can anyone help?

Have you just installed IE7 ?

The only reference to this I have seen is that it happens if you install IE7 and don't reboot immediately after.
The advice was to uninstall IE7 (control panel add/remove programs) and reinstall it and reboot as soon as it completed.

I don't use IE7 so I can't test it out myself and all the advice was from 2007

Nooo, get Google Chrome.

At the very least get shot of IE7. It's evil