It works here on my machine with Windows 2000. Perhaps you have deselected "Show Abort Button" under "VI Properties>>Window Appearance>>Customize..." If this option is not checked then Ctrl + . will not work. If you do not want to show the Abort button but still want Ctrl + . to work then uncheck the "Show Toolbar When Running" option.
Thats interesting, maybe there is some other process running that is capturing that key stroke? I tried a bunch of different things and couldn't get "Ctrl+." to not work on my Windows2000 machine.
I have resolved the problem. "Ctrl + ." work on my Windows2000 machine only with the point of the numeric pad ("," del). Thank you very much. Regards, Roberto