Have a legacy app that has been running fine on IIS6 Windows 2003 server. Redeployed to Windows 2012 server with IIS 8.5 and now all requests get a HTTP 401.2 error.
The site is assigned to its own app pool which is a .net4 Classic using local Network Service account as identity. The site is set for Forms Authentication enable all others are disabled.
Local Network Service account has access to wwwroot directory.
The code deployed works fine when run in debug mode on my local development pc.
I am at a loss as to how to troubleshoot and fix this issue.
Note: although the app uses Forms authentication it does pick-up the logged on user's credentials to check if the user exists in the aspnet tables. It gets the credentials using Request.ServerVariables("LOGON_USER").split("\")(1).ToUpper()