Cannot open database \"mydb\" requested by the login. The login failed.\r\nLogin failed for user 'IIS APPPOOL\\ASP.NET v4.0'
Error: Cannot open database \"MYDB\" requested by the login. The login failed.\r\nLogin failed for user 'IIS APPPOOL\\ASP.NET v4.0'."} Try: Note 'IIS APPPool' in the error - it is looking for 'NETWORK SERVICE' to be set as identity. To do this, Go to : IIS Manager > Application Pools > Select - Your Application Pool (That you have mapped to your application , like ASP.NET v4.0) On the RHS > Click 'Advanced Settings' > Look For 'Process ' > 'identity' > From the dropdown Select 'NETWORK SERVICE' > click OK. Now try running your application.