unable to login to sqlserver 2005

Question

TITLE: Connect to Server

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Cannot connect to USER.

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ADDITIONAL INFORMATION:

Login failed for user 'sa'. (Microsoft SQL Server, Error: 18456)

For help, click: http://go.microsoft.com/fwlink?ProdName=Microsoft+SQL+Server&EvtSrc=MSSQLServer&EvtID=18456&LinkId=20476

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