Can't add more users in Visual SourceSafe 6.0d

Hi.

I'm trying to add a user to a VSS database, but when I enter the name
and push the Ok button in the dialog box, the first time create the
folder ...\users\user_name, and the said:

cannot access to DOS Path: \\server\VSS\users

The second time that I try to add the user it says: username folder
exists, and the can access DOS Path ...

\\server\VSS is a shared folder in a remote machine running Windows
2003 Server Standard Edition
I run the Visual SourceSafe admin in a Windows 2000 Professional SP4

I check the security permission and it's ok. I tried to add the user
even with the domain administrator and show me the same error message.

Thanks in advanced