Completely Disable the System Tray on Windows Vista / XP

Open up regedit.exe through the start menu search or run box, and then navigate down to the following key (Create if it doesn't exist):

HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Policies\Explorer

Create a new 32-bit DWORD value in the right hand pane with these values:

• Name: NoTrayItemsDisplay
• Value: 1

You will have to logoff and back on for this to take effect. To remove the hack, just delete the key, or change the value to 0.

Note that disabling the system tray doesn't actually prevent system tray apps from running, it just hides them. You should still disable any applications that aren't needed.

Update: Note that the same registry key may exist in more than one location, so if you are trying to reverse this hack, you should search the registry for NoTrayItemsDisplay.