The problem you're describing is addressed in the MSKB article below. It includes sample code that you can download.

SAMPLE: Disable.exe Example Enables/Disables Menu Pads and Bars

>asked this several weeks ago, but am asking again. hoping to jar someones memmory.
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>have a toplevelform with a menu from the menu designer. when i change the values of my skip for variable, the menu items do not turn grey/black as appropriate. i can not "activate menuname" because i do not know the menu name. the menuname is a local variable created with a sys(2015) in the .mpr.
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> _msysmenu i believe has no bearing. believe it is only relevant to the vfp _screen. so "activate _msysmenu" does nothing for me. Neither does push/pop _msysmenu. i've tried all three.
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>any ideas. thanks - brenda