Vista - Can't add the url to my WSS 3.0 site

Hi,
This one has been plaguing me for awhile now, and I have searched and
searched and can't come up with an answer or reason for the behaviour.

When working on my Vista Business workstation, I have tried adding the url
to my WSS 3.0 document workspace using the "add Network Location" wizard,
but it keeps coming back with the following error message after asking for
my credentials three times:

"The folder you entered does not appear to be valid. Please choose
another."

Now this by itself wouldn't be so bothersome if it was the only "security"
problem that was occurring. When I click on a Word or Excel document in the
workspace, the corresponding application opens. Of course since I didn't
check it out before opening the doc, after it's opened I have a banner at
the top of the doc that reads "Server Document to modify this document,
click Edit Document" and there is a corresponding button. When clicked I
click the button, I am authenticated three times and the receive the
following error:
"Unkown error trying to lock file."
When I click ok on the error message I'm back to where I started before.

I realize that I can work around these challenges, but it frustrates me
becuase this isn't how the system is supposed to work and it is maddening
not being able to find the answers anywhere. So I am really hoping the
this collective might have overcome these problems, and can point me in the
right direction.

TIA!

Art Billings