Latitude D420 LCD Projector problem

I have an issue with a D420 that has got me stumped.

 

When I connect an LCD projector(any LCD projector) to the external VGA port on the laptop, the diplay sets up properly....until I try to use any Microsoft Office application, then the fun starts.

 

If I start Excel, as soon as I click anywhere in the pane, the display zooms up to 250%

 

If I start Word, it zooms up to 500%!

 

Powerpoint is 200%

 

Access the same.

 

If I remove the the LCD projector, it stays that way until I reboot.

 

I cannot reduce the zoom from maximum until the PC is rebooted.

 

I've tried reinstalling video drivers, reinstalling Office, with no luck.

 

Any help will be greatly apprecicated!