Sudden error in making connection [duplicate]

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• A connection was successfully established with the server, but then an error occurred during the pre-login handshake 15 answers

I am using SQL Server 2008 Enterprise edition. My instance name is saboor-pc/ SQLSERVERENT. I have been using this server for many months and I am satisfied.

But today an unexpected error occured when I clicked on "connect" button in SQL Server Management Studio.

Error message:

Cannot connect to SABOOR-PC/MSSQLSERVERENT

A connection was successfully established with the server, but then an error occured during the pre-login handshake(provider: SSL Provider, error:0 The message recieved was un expected or badly formatted)(MicroSoft SQL Server)

Please guide me how can I solve this error because I have to do important work on database which I have created in this server.