I'm trying to connect a Server 2008 R2 NPS to a MSSQL server for logging accounting data and I'm running into issues.

I configured NPS Accounting through the "Configure Accounting" wizard and, using windows integrated security, I was able to connect to my MSSQL server (2012 express) and create a DB for accounting.

When I test it out though my NPS generates a 6274 event: "... could not be written to the configured accounting datastore".

Looking on my DB server I see a 18456 event: "Login failed for user 'mydom\npsserver$'. Reason: Failed to open the explicitly specified database 'myNPSDB'. [CLIENT: NPS.servers.IP.addr]"

So even though I setup the DB connection with a domain account with DB access the server is connecting with the local machine account.

I don't want to give my NPS server's computer account explicit access to my DB and want to use a domain account instead.

When in the Data Link Properties dialogue box I tried to enter a domain account with "Use a specific user name and password", but I get a "Login failed for user" error- I know the credentials I typed in were correct.

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I then tried running the Network Policy Server service as a domain account, but after doing this it would not start.

How can I get my NPS to connect to my DB with a domain account?


Make sure your SQL instance is using mixed mode authentication. By default SQL is installed using Windows authentication only.

From this MSDN page:

To change security authentication mode

In SQL Server Management Studio Object Explorer, right-click the server, and then click Properties.

  • On the Security page, under Server authentication, select the new server authentication mode, and then click OK.
  • In the SQL Server Management Studio dialog box, click OK to acknowledge the requirement to restart SQL Server.
  • In Object Explorer, right-click your server, and then click Restart. If SQL Server Agent is running, it must also be restarted.

To enable the sa login

  • In Object Explorer, expand Security, expand Logins, right-click sa, and then click Properties.
  • On the General page, you might have to create and confirm a password for the login.
  • On the Status page, in the Login section, click Enabled, and then click OK.
  • OK, but I want to use a domain account not an SQL account. I'm also going to edit my post with more info on my issue. – red888 Feb 24 '15 at 21:14
  • OK I updated my post specifically asking how to do this with a domain account. – red888 Feb 24 '15 at 21:18
  • @red888 You have to use Windows authentication in order to use a domain account. If you want to use a different domain account than the one you're logged in as you need log out and log back in with that account or run SQL Server Management Studio as the other account (using the Run As function). – squillman Feb 24 '15 at 21:50
  • I already said its not using the user's domain credentials when trying to access the SQL DB. I can use Windows authentication when setting up the connection, but when the NPS server tries to access the SQL server to log data it uses its domain computer account. – red888 Feb 25 '15 at 13:36

I have managed to make this work by adding the computer account dbo permissions on the NPS Accounting database. As you cannot searcht he cmputer account when creating a new login using SQL Management studio, you have to manually type the account as domain\computername$ and grant the dbo permission for the NPS Accounting database. It's a bit tedious if you have multiple RADIUS servers trying to log their transactions to SQL but at least it works.

I also tried using a computer group but this is not successful.

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