SQL Server 2008 windows authentication problems

I have a timeclock database set开发者_如何学Pythonup on a Windows 2008 server, SQL Server. It has been working for MONTHS. Today, all of a sudden, it seems like some peoples' logins are working and some peoples' logins are not working.

SQL authentication works fine, however the Windows authentication is not working. I checked the log files and it seems like SQL Server 2008 is just not liking the passwords!

Does anyone know what could be going on here?

Windows auth relies on the SIDs contained in the login token generated when folk log in to Windows: not the actual windows password or even username

If it's failing, then you have issues witg Active Directory or some underpinnings such as Kerberos.

Saying that, there are some common issue I've seen over time:_

• password changes: invalidate the login token in some circumstances. If you have a policy for password changes then simply sking folk to lock/unlcok their PCs will cause a "re-login" against AD

• use FQDN + port: If you use named instance, the client must query port 1434 to get the actual port of the instance. If you have a lot of firewalls or remote clients then sometimes this handshake fails. IIRC something to do with Kerberos. We found using server.domain.tld\instance, port fixed all our issues (I'm talking USA or Hong Kong to Europe based server)

You may solve this problem by assigning user rights to the user: "NT AUTHORITY\SYSTEM". Follow these steps:

1. Open "SQL Server Management Studio".
2. Open "Security, and then Logins".
3. Rightclick on user: "NT AUTHORITY\SYSTEM >> Properties".
4. Select "Server Roles" tab, and check the "sysadmin" server role.

You are done.

u can also try right click on the user u wanna grant the privilegies and click on all of them in server roles