Cannot add an account [non domain account ] to SQL Server 2012 Background:

I have a application pool [ABCDEMO] in IIS. The identity of the appool is "NetworkService". I am trying to add IIS APPPOOL\ABCDEMO to my SQL SERVER 2012 on a Windows SERVER 2012.

When I try to add to the Logins I get the following error.

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Create failed for Login 'IIS APPPOOL\ABCDEMO'.  (Microsoft.SqlServer.Smo)

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For help, click: http://go.microsoft.com/fwlink?ProdName=Microsoft+SQL+Server&amp;ProdVer=11.0.2100.60+((SQL11_RTM).120210-1917+)&amp;EvtSrc=Microsoft.SqlServer.Management.Smo.ExceptionTemplates.FailedOperationExceptionText&amp;EvtID=Create+Login&amp;LinkId=20476

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Program Location:

   at Microsoft.SqlServer.Management.Smo.SqlSmoObject.CreateImpl()
   at Microsoft.SqlServer.Management.SqlManagerUI.CreateLoginData.LoginPrototype.ApplyGeneralChanges(Server server)
   at Microsoft.SqlServer.Management.SqlManagerUI.CreateLogin.DoPreProcessExecution(RunType runType, ExecutionMode&amp; executionResult)
   at Microsoft.SqlServer.Management.SqlMgmt.SqlMgmtTreeViewControl.DoPreProcessExecutionAndRunViews(RunType runType)
   at Microsoft.SqlServer.Management.SqlMgmt.SqlMgmtTreeViewControl.ExecuteForSql(PreProcessExecutionInfo executionInfo, ExecutionMode&amp; executionResult)
   at Microsoft.SqlServer.Management.SqlMgmt.SqlMgmtTreeViewControl.Microsoft.SqlServer.Management.SqlMgmt.IExecutionAwareSqlControlCollection.PreProcessExecution(PreProcessExecutionInfo executionInfo, ExecutionMode&amp; executionResult)
   at Microsoft.SqlServer.Management.SqlMgmt.ViewSwitcherControlsManager.RunNow(RunType runType, Object sender)

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An exception occurred while executing a Transact-SQL statement or batch. (Microsoft.SqlServer.ConnectionInfo)

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Program Location:

   at Microsoft.SqlServer.Management.Common.ServerConnection.ExecuteNonQuery(String sqlCommand, ExecutionTypes executionType)
   at Microsoft.SqlServer.Management.Common.ServerConnection.ExecuteNonQuery(StringCollection sqlCommands, ExecutionTypes executionType)
   at Microsoft.SqlServer.Management.Smo.ExecutionManager.ExecuteNonQuery(StringCollection queries)
   at Microsoft.SqlServer.Management.Smo.SqlSmoObject.ExecuteNonQuery(StringCollection queries, Boolean includeDbContext)
   at Microsoft.SqlServer.Management.Smo.SqlSmoObject.CreateImplFinish(StringCollection createQuery, ScriptingPreferences sp)
   at Microsoft.SqlServer.Management.Smo.SqlSmoObject.CreateImpl()

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Windows NT user or group 'IIS APPPOOL\ABCDEMO' not found. Check the name again. (.Net SqlClient Data Provider)

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For help, click: http://go.microsoft.com/fwlink?ProdName=Microsoft%20SQL%20Server&amp;ProdVer=11.00.2100&amp;EvtSrc=MSSQLServer&amp;EvtID=15401&amp;LinkId=20476

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Server Name: USALVWCOQA10
Error Number: 15401
Severity: 16
State: 1
Line Number: 1


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Program Location:

   at Microsoft.SqlServer.Management.Common.ConnectionManager.ExecuteTSql(ExecuteTSqlAction action, Object execObject, DataSet fillDataSet, Boolean catchException)
   at Microsoft.SqlServer.Management.Common.ServerConnection.ExecuteNonQuery(String sqlCommand, ExecutionTypes executionType)
It's probably because that's not the way that the SQL Server instance is seeing the application.  Attempt to use the application.  This should log an error in the SQL Server's ERRORLOG file when the application isn't able to connect.  This will tell you how the SQL Server is seeing the login.  Just copy the login from the ERRORLOG file and create a login for it.