Running explorer in new desktop

I create in my Application a new desktop and run in it explorer with the parameters:
explorer /e,/root,c:\.
At first time after loading OS explorer is fault and the following dialog is opened:

title - /e,/root,c:\
Messsage: - Window can not find "/e,/root,c:\". Make sure you typed the name correctly and then try again. To search for a file click the Start button and then click Search.

I close this dialog and continue and after that all running explorer is right.

Very weird why explorer is fault at first time after loading OS.
May be anybody guesses whats reason?

How are you creating the Explorer.exe process? I mean which API, what arguments?

Looks like "explorer.exe" argument is treated as null.

I use
CreateProcess(.....)
and run "explorer.exe /e,/root,c:\"