I added the user, but I'm still getting

'The user is not associated with a trusted SQL Server connection.'

Do you know what should I do to make it work?

Thanks in advance.

I've tried to log through SSMS for this user and got

TITLE: Connect to Server
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Cannot connect to < Server name >

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ADDITIONAL INFORMATION:

A connection was successfully established with the server, but then an error occurred during the login process. (provider: Shared Memory Provider, error: 0 - No process is on the other end of the pipe.) (Microsoft SQL Server, Error: 233)

For help, click: http://go.microsoft.com/fwlink?ProdName=Microsoft+SQL+Server&EvtSrc=MSSQLServer&EvtID=233&LinkId=20476

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BUTTONS:

OK
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