Login failed. Login failed for user 'NT AUTHORITY\SYSTEM'

Question

I have created a windows service & my service is dependent on the SQL server service. First, SQL started and then my service started when starting PC or restarting PC.

This works fine but the issue is database file can not be read by the Windows service, throwing the exception "Cannot open user default database. Login failed.Login failed for user 'NT AUTHORITY\SYSTEM' " when i am trying to read the database.

If I start the computer & login then it can not read the database, but if i have start the computer & wait for a few seconds and then log into the window service it reads the database.

Answer 1

I bet you have this in your connection string:

Integrated Security=SSPI

or something similar.

Now the account that service is running under (NT AUTHORITY\SYSTEM) tries to connect to the database - and can't since it's not authorized to do so.

You can:

• either create a login for NT AUTHORITY\SYSTEM in your SQL Server and give it the necessary permissions it needs for your app

OR:

• you create a specific application user account in SQL Server (login to SQL Server and user in your database) and change your connection string to:

  User ID=(your app account);pwd=YourPassword