Login failed for user 'IIS APPPOOL\ASP.NET v4.0'. Description: An unhandled exception occurred during the execution of the current web request. Please review the stack trace for more information about the error and where it originated in the code. Exception Details: System.Data.SqlClient.SqlException: Login failed for user 'IIS APPPOOL\ASP.NET v4.0'.
When we are calling to database through our programs, some times we will get Login failed for user 'IIS APPPOOL\User'. we can resolve this one using below small settings.
Open IIS 7 --> Application Pools (left side) --> select application pool --> open advance settings --->change identity to localSystem.
Please refer below image for reference
|IIS User login failed|