problem in connection to the server

i am trying to connect to sql server on 2005 express. but i cant connect to it, the log error is
if you can explain to me how can i solve this?




TITLE: Connect to Server
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Cannot connect to M-FAC95211BECB4\SQLEXPRESS.

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ADDITIONAL INFORMATION:

Login failed for user 'M-FAC95211BECB4\vitaly87'. Reason: Server is in single user mode. Only one administrator can connect at this time. (Microsoft SQL Server, Error: 18461)

For help, click: http://go.microsoft.com/fwlink?ProdName=Microsoft+SQL+Server&EvtSrc=MSSQLServer&EvtID=18461&LinkId=20476

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BUTTONS:

OK
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