🚀 go-pugleaf

Hi guys - hopefully the final post for a few days - I think I nearly have my 
system working.

I have one last questions, maybe someone could give me a few ideas.  I'm 
just looking for some design suggestions.

The background to my problem is as follows.  I currently have a GinaStub 
that runs under the context of the LocalSystem, in time though, this will be 
replaced with a service.  In either case, the system controls access to a 
given computer and controls what can be done on that computer, based on the 
logged on user.

When a user logs on, a system tray icon / application is launched based on 
the [HKLM] Run registry key.  When a user double-clicks on this icon, an IPC 
message is sent to the GinaStub / Service which then uses 
CreateProcessAsUser to launch a configuration application. This system all 
works fine and seems to hold water with Fast-User switching.

However, I now have a small issue.  Firstly, I want to ensure that only one 
occurrence of this Control application is launched per logged on user.  As 
it stands, if a double-click on the icon more than once, I get another 
occurrence of the control app launched.  I don't think that I can use the 
normal mutex system for ensuring single occurrence because this mutex may 
have been created by a control app on another users desktop.

Does this make any sense?  Does anyone have any suggestions?

Cheers, Mike C