Starting with Windows Vista and Server 2008, Microsoft changed the way services are allowed to interact with the desktop. They decided that for security reasons, services are now only allowed to show their GUI on a special desktop that only the service can interact with. Unfortunately, this makes interactive features pretty much useless. We are looking into ways to display a GUI in a different way. Stay tuned.

If you do a search on the Internet with keywords of "Interactive services dialog Vista", you will find a number of references to the way Windows will display a dialog on the user desktop whenever a service has updated into GUI on the services desktop.

There are some important security reasons why this was disabled in Windows. But if you really need to reenable this functionality, it is possible to do so by editing the Windows Registry and setting HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Windows\NoInteractiveServices to 0. Always be very careful editing the registry as you can easily mess up your system by changing the wrong values.

On Windows XP, it is possible for multiple users to be logged in locally at the same time. Windows Services only have access to the desktop of the first user.

Desktops created with the Remote Desktop tool do not appear to ever be accessible by interactive services. Other tools which are actually mirroring the local desktop will have access as Windows thinks it is rendering the local desktop.

This property must be set to FALSE if the service is configured to run using a specific account in the wrapper.ntservice.account property.

Changes on this property will not take effect until the Windows Service is reinstalled.