"The specified procedure cannot be found" error when opening project from source control

Hi all,

When I try to open an project from source control(VSS 6.0) in my vs.net 2003, the following message occour:
"The specified procedure cannot be found"
and it cannot be opened."

I can open that project from local working folder.but whenever I try to checkout a file, that error message occours but I can procceed to check out that file.

But I cannot still open a new project from source control!

I have tried to
   1)uninstall and reinstall VSS
   2)uninstall VSS and reinstall vs.net 2003 and install VSS
   2)uninstall VSS, uninstall vs.net 2003 and install vs.net 2003 and VSS
but not success to open a new project from source control and that error message still occour!

Thanks in advance
TTW