@Tom: I think you may be able to enable/install the WebDAV role services, then disable them for just the SmarterMail site potentially. While we do both use WebDAV, I think the base IIS services and the SmarterMail DAV services might be conflicting. Can you check to see if this is a possibility?
Kyle Kerst
System/Network Administrator
SmarterTools Inc.
(877) 357-6278
www.smartertools.com