Strange issue - dialog boxes and menus disappear

[aeonaero]

When I connect to a pc (both xp and w7), everything works perfectly with one exception. Programs that open a dialog box, or any menu simply disappear. It's like Teamnviewer is sending an esc key command to the host. It only happens from one viewer pc to any other machine.

I have removed Teamviewer (Both ver 6 and a previous ver 5 install) including all settings. After reinstall, the behavior returns. I have verified my settings on this machine match the settings on my other machines, so unless I missed something, I don't think it's a settings issue.

Has anyone seen anything like this before?

Thanks a heap!

Dan