Login failed for user 'DOMAIN\MACHINENAME$'

NETWORK SERVICE and LocalSystem will authenticate themselves always as the correpsonding account locally (builtin\network service and builtin\system) but both will authenticate as the machine account remotely.

If you see a failure like Login failed for user 'DOMAIN\MACHINENAME$' it means that a process running as NETWORK SERVICE or as LocalSystem has accessed a remote resource, has authenticated itself as the machine account and was denied authorization.

Typical example would be an ASP application running in an app pool set to use NETWORK SERVICE credential and connecting to a remote SQL Server: the app pool will authenticate as the machine running the app pool, and is this machine account that needs to be granted access.

When access is denied to a machine account, then access must be granted to the machine account. If the server refuses to login 'DOMAIN\MACHINE$', then you must grant login rights to 'DOMAIN\MACHINE$' not to NETWORK SERVICE. Granting access to NETWORK SERVICE would allow a local process running as NETWORK SERVICE to connect, not a remote one, since the remote one will authenticate as, you guessed, DOMAIN\MACHINE$.

If you expect the asp application to connect to the remote SQL Server as a SQL login and you get exceptions about DOMAIN\MACHINE$ it means you use Integrated Security in the connection string. If this is unexpected, it means you screwed up the connection strings you use.

This error occurs when you have configured your application with IIS, and IIS goes to SQL Server and tries to login with credentials that do not have proper permissions. This error can also occur when replication or mirroring is set up. I will be going over a solution that works always and is very simple.Go to SQL Server >> Security >> Logins and right click on NT AUTHORITY\NETWORK SERVICE and select Properties

In newly opened screen of Login Properties, go to the “User Mapping” tab. Then, on the “User Mapping” tab, select the desired database – especially the database for which this error message is displayed. On the lower screen, check the role db_owner. Click OK.

Basically to resolve this we need to have some set up like

• Web App Running under ApplicationPoolIdentity
• Web Application connecting to databases through ADO.Net using Windows Authentication in the connection string

The connection string used with Windows authentication include either Trusted_Connection=Yesattribute or the equivalent attribute Integrated Security=SSPI in Web.config file

My database connection is in Windows Authentication mode. So I resolved it by simply changing the Application Pools Identity from ApplicationPoolIdentity to my domain log in credentials DomainName\MyloginId

Step:

1. Click on Application Pools

2. Select Name of your application

3. Go to Advanced Setting

4. Expand Process Model and click Identity. Click threedot on right end.
5. Click Set... button and Provide your domain log in credentials

For me it was resolved.

Note: In Production or IT environment, you might have service account under same domain for app pool identity. If so, use service account instead of your login.