Preventing office from using MSDAIPP

Question

I have a drive letter mounted to a webdav url (using basic authentication), I pass the credentials when executing the net use command. This is all working fine, when looking at my tcpdump i can see how every request is done by Microsoft-WebDAV-MiniRedir. Also the credentials are correctly passed every time.

However when I open an office file the request are no longer done by Microsoft-WebDAV-MIniRedir but by MSDAIPP (Microsoft Data Access Internet Publishing Provider). Clearly office starts accessing the webdav directly, since office has build in webdav support (ie MSDAIPP).

However my credentials are passed while creating the mount using the miniredir, MSDAIPP does not have my credentials. So office will ask for the credentials himself.

I want office to not access webdav himself but just to access it through the driveletter (in which case it will be handeld by the miniredir).

I'm 100% sure this is the problem, I can open the .doc file using notepad or whatever and save it. So I'm certain it has to do with MSDAIPP taking over.

Since I'm working on a product which will automaticly create a webdav drive letter for the user, the user itself is actually unaware of his credentials (they are generated). Therefore it is unacceptable for the users to fill in their credentials in office.

Being able to automaticly pass the credentials to MSDAIPP would also be fine.

Thanks in advance.

Answer 1

As far as I know this is a Microsoft Office limitation and there is no any solution. Microsoft Office will always ask for credentials when using Basic or Digest authentication.

I see the following workarounds:

• Implement URL authentication. Put some id into the Url (but not into the query string, it will be truncated by MS Office), like this: http://serv/SessionID1234567890/folder/document.doc.
• Use Windows Integrated Authentication, that is NTLM or Kerberos. Microsoft Office will not ask for authentication in this case.