Re-enabling Aero Glass without rebooting, after an app disables it

I've got a stable Windows 7 Ultimate (x64) system. It's a Dell Vostro 410, 8GB RAM, Intel Core 2 Quad CPU @2.4GHz, WEI of 3.7. The on-board video adapter is an ATI Radeon HD 2400 PRO with 128MB of dedicated video memory. I have two monitors, one connected to DVI and one to VGA.

Aero Themes work just fine on both monitors, I get Glass, Peek, all the goodies normally.

From time to time, I have to do one of the following:
  • share my screen with GoToMeeting
  • share my screen with Microsoft SharedView
  • log in to my machine remotely with Remote Desktop, then later return home and log in normally
Doing any of these three things disables Aero Glass; I can readily understand that. What I can't understand is why there is no way to get it back without rebooting.

Rebooting brings it back just fine, but I don't see why it's necessary.

Things I have checked while Glass is temporarily disabled:
  • Changing the theme to Windows Basic, then changing it back to the stock Windows 7 Aero theme does not re-enable Glass.
  • The Aero Troubleshooter ("Find and fix problems with transparency and other visual effects") finds no issues.
  • The Desktop Window Manager Session Manager service is running. Restarting it does not re-enable Glass.
  • My video driver is up to date according to Windows Update. (Dell does not officially support Windows 7 on the Vostro 410, so I can't get a driver there. But it's working just fine, dammit.)

Clearly, these screensharing programs, and remote desktop, are doing something, perhaps to the video driver, to tell it not to use Glass. How can I tell it to start using it again?

This website is not affiliated, owned, or endorsed by Microsoft Corporation. It is a member of the Microsoft Partner Program.