System Events actions triggered from Outlook Script Menu don't work

Here’s a simple script to bring the main window to the front:

tell application "Microsoft Outlook"
    activate
    set WindowName to name of first main window
    tell application "System Events"
        tell process "Microsoft Outlook"
            click menu item WindowName of menu 1 of menu bar item "Window" of menu bar 1
        end tell
    end tell
end tell

This script works fine when triggered from within the ApplleScript Editor, or when triggered via a QuicKeys shortuct.

HOWEVER, if you put it in in the Outlook Script Menu Items folder and trigger it by selecting it from Outlooks Script Menu, it fails with the error:

“System Events can’t get menu bar 1 of process “Microsoft Outlook”. Invalid Index”

Does anyone have any idea why this is happening and how to make it so such scripts will work from the Outlook Script Menu???