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Login failed to connect to SQL Server

The OS’s edition is professional,The SQL Server is Deskop editon of 7.0+SP4.
when I try to connect to the Server ,It’s show me a error message like this: Unable to connect to Server\172.17.8.166:
Server:Msg 18452,Level 16,State 1
[Microsoft][ODBC SQL Server Driver][SQL Server]Login failed for user ‘sa’.
Reason:Not associated with a trusted SQL Server connection. I double-checked the LoginMode is SQL Server and Windows NT.then why do I get this error?
Help me please. Thanks very much¡T
Jelly.
Hi Jelly, What are you using to attempt to connect to SQLServer? Could it be that a connection string is used and it has set both a user id and trusted connections? Otherwise, if you have changed SQL Server’s login mode, then you’d need to restart SQLServer Cheers
Twan
This problem is more likely to occur when both Multi-Protocol and TCP/IP sockets trusted connections are attempted from the same client computer. Connection stress also makes the problem more likely to occur. Use one of the following workarounds:
– Use trusted connections over named pipes where appropriate.
– Disable multiprotocol for SQL Server using the Server Network Utility.
_________
Satya SKJ
Moderator
SQL-Server-Performance.Com

Hi Twan and satya,
thanks for your help,I solved this problem yet.Guess what did i do about it? Just restart the computer!But I unknown why do i need to restart ?maybe the OS’s edition is lower?? Jelly.
As Twan said, maybe you’ve changed the login mode from ‘Windows only’ to ‘Mixed’ mode. When you do this you must re-start SQL server for the changes to take affect.
I think Jelly hasn’t changed the authentication mode after this post, it seems the restart corrected the issue. _________
Satya SKJ
Moderator
SQL-Server-Performance.Com

It’s not after this post Satya, He might have changed it before this post but never re-started the server to take that setting into affect. How else a re-start can fix this issue ?
Well for such issues I’m sure restarting SQL Services will definetly help and it proved many time at my end. As you prescribed for any configuration changes a restart is must to affect. _________
Satya SKJ
Moderator
SQL-Server-Performance.Com

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