I am trying to share a Vista drive from a DOS based embedded system using SMB with the "PC network program 1.0" dialect, but get an "Access denied" error.

The "Negotiate Protocol Request" for the "PC network program 1.0" Dialect (2), is acknowledged without an error with a "Negotiate Protocol Response" from Vista, but the "Tree connect Request" receives a "Tree connect Response" with an error code of 1 - Access denied".

The Vista shared drive is shared with Password protected sharing Off and all permissions on. I have tried both Public and a shared folder as well; same problem. Have also tried with password for user defined on Vista; no go.

Using the same DOS client to WinXP works fine.
Running Vista Business - no SP.
Firewall is turned off.
Connection from WinXP works fine; obviously using a newer dialect.

Is there a solution to this problem?

Many viewers, zero answers

Some more info: I installed SP1; still not working...