While doing some experiment with magnifier in windows .I change setting dock 2 full screen to this future of magnifier . Doing so disables Desktop Window Manager which is necessary for Windows Aero to run. To return the magnifier to full screen Aero has to be operational. When I get Aero running again through the troubleshooting system in the Personalization area of the fixing transparency issues in control panel . it works fine, until the magnifier is opened again and it starts up in dock mode, disabling the DWM and Aero from menu.
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