Creating an instance of MS Project Application fails in VB .Net

In my VB .Net code, I am trying to create to launch MS Project Application.
Dim prjApp As Microsoft.Office.Interop.MSProject.Application = New Microsoft.Office.Interop.MSProject.Application

But I am getting the exception as follows:

"Creating an instance of the COM
component with CSSID {36D27C48-A1E8-11D3-BA55-00C04F72F325} from the
IClassFactory failed due to the following error: 80010001".

Note: This exception happens in 64 bit Windows 7 German OS. But the same code runs successfully in 32 bit Win XP (German and English) and 64 bit Windows 7 English OS.

I have even tried the following steps in German 64 bit Win 7
1. Running the application in Administrator mode
2. Setting UAC to low.
3. Re-installing MS Project in German 64 bit Win 7.

But still the problem occurs. Can some one please help me in resolving this issue.

The Office Interop version on the "64 bit Windows 7 German OS" is older that the version on the developing system...

see this MSDN Thread for more info..