• A web server (Windows 2012 R2, IIS 8.5) outside of domain (called MY_WEB_SERVER)
  • A virtual directory pointing to a NAS server on a domain (called MY_NAS_SERVER)
  • An application set on virtual directory to give the virtual directory its own app in the app pool (called AccessNAS)

Problem: The credentials are rejected by the NAS server, most likely because the ones IIS sends are not the ones we want it to send.

I have configured the app in app pool with a custom identity (username: MY_NAS_SERVER\nas_account). This account exists on the NAS. However, the connection is refused. If I look at ProcMon, I see two ACCESS_DENIED notices on CreateFile, and they both were attempted not using my given custom identity, but "MY_WEB_SERVER\nas_account".

How do I prevent the substitution of "MY_NAS_SERVER" with "MY_WEB_SERVER", so that the credentials I provide are the ones used?

And can this be done without a web.config file on the NAS server?

  • Have you tried creating a local account on the web server and the NAS server both with the same username and password? Then set the app pool to use that username and password. – Mass Nerder Jan 12 '16 at 19:54
  • @MassNerder Yes, that was my first attempt, but what I see in ProcMon is the Web server sending "MY_WEB_SERVER\nas_account" rather than "nas_account" or "MY_NAS_SERVER\nas_account". The NAS server refuses the "MY_WEB_SERVER\nas_account" name. – MPelletier Jan 12 '16 at 20:12
  • What about doing something like logging on as the app pool user, mapping a drive to to the NAS, then point your config to the drive. – Mass Nerder Jan 13 '16 at 16:14
  • @MassNerder That was suggested (and I really wanted that TBH) but rejected for other reasons. Namely that they want IIS to control everything. – MPelletier Jan 13 '16 at 16:38
  • have you tried using ".\username" in the app pool identity? – Mass Nerder Jan 13 '16 at 17:36

IIS app pool has never worked as its advertised for me either. You can't configure an app pool to a specific user and then access a file share with pass-through authentication. You need to add specific user path credentials for each virtual directory.

  • Even so, this too fails. – MPelletier Jan 12 '16 at 22:35
  • Try changing to specific user path credentials and then redo the ProcMon. You should also try connecting as WORKGROUP\nas_account instead of MY_NAS_SERVER\nas_account. – BruceLeroy Jan 12 '16 at 22:56
  • A workaround has been found, namely that the web servers were put on the domain. I couldn't test your solution. I really wanted to (with the workgroup). I'm giving you the prize nonetheless for your time. – MPelletier Jan 13 '16 at 16:39

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.