Remote UI script with windows 7 logged off - PSEXEC.

I am using psexec to run a remote script which does some UI operations on the print objects present in the remote system. To be specific , the API used is SHInvokePrinterCommand() to invoke printer properties of a printer object.

The entire thing works fine when executed with a user logged in(and thus a visible desktop) on windows 7. But when no user is logged in , the procedure is failing to work, the API(SHInvokePrinterCommand) returns successfully but it doesn't seem to do any work. WINDOWS XP under the similar conditions, WORKS FINE.

The observation made me believe that it has something to do with the session and "Window station" architecture that varies within these operating systems.
With some coding in the remote process , I was able to establish that the remote process is started in a non-zero session (session 2) by psexec and the only window station it is attached to is "WinSta0".(I used EnumWindowStations() for that). WinSta0 is the only windows station which receives input from KeyBoard , mouse etc.

With this much observation , I fail to understand what makes the entire thing not work in case of windows 7, with no on logged in. Basically the properties page of printer is not actually getting invoked in this case.
Does the session , that psexec forms , for executing the remote process ,in some way not a "complete" session? Any way to fix this problem?

Any ideas or suggestion are most welcome.