How to access a running instance of SQL Server Database Engine to troubleshoot MSSQL with SQL Server Management Studio

When the SQL Server becomes very slow or unresponsive meaning the MSSQL is running 100% but nothing is happening. Microsoft does not want to call this hanged.
You try to log with the SQL Server Management Studio and can't.
Microsoft provides the Dedicated Administrator Connection or DAC.
The Dedicated Administrator Connection allows the administrator or anybody part of the sysadmin group to log in even when nobody else can.
The Dedicated Administrator Connection allows the administrator or anybody part of the sysadmin group to close other people connections... and resolve the issues including restarting the SQL Server.

Applies to:

Microsoft SQL Server 2005
Microsoft SQL Server 2008

Connecting with the Dedicated Administrator Connection with SQL Server Management Studio

Select the Database Engine Query icon:

Database Engine Query icon

In the Connect to Database Engine dialog box

Connect to Database Engine dialog box

Use admin: with the colon : followed by the name of the server instance.

Connect to Database Engine with ADMIN:

You must provide the credentials [username/password] of somebody that is a member of the sysadmin group.

There is only 1 Dedicated Administrator Connection allowed.
If the Dedicated Administrator Connection is already used, it will fail.

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Home page Administration Dates & Times Data Manipulation FAQs Optimization Summaries Site Map About us About us Copyrights Credits Disclaimers Guaranties Privacy Support policies Feedback	Administration How to access a running instance of SQL Server Database Engine to troubleshoot MSSQL with SQL Server Management Studio How to access a running instance of SQL Server Database Engine to troubleshoot MSSQL with SQL Server Management Studio When the SQL Server becomes very slow or unresponsive meaning the MSSQL is running 100% but nothing is happening. Microsoft does not want to call this hanged. You try to log with the SQL Server Management Studio and can't. Microsoft provides the Dedicated Administrator Connection or DAC. The Dedicated Administrator Connection allows the administrator or anybody part of the sysadmin group to log in even when nobody else can. The Dedicated Administrator Connection allows the administrator or anybody part of the sysadmin group to close other people connections... and resolve the issues including restarting the SQL Server. Applies to: Microsoft SQL Server 2005 Microsoft SQL Server 2008 Connecting with the Dedicated Administrator Connection with SQL Server Management Studio Select the Database Engine Query icon: Database Engine Query icon In the Connect to Database Engine dialog box Connect to Database Engine dialog box Use *admin:* with the colon : followed by the name of the server instance. Connect to Database Engine with ADMIN: You must provide the credentials [username/password] of somebody that is a member of the sysadmin group. There is only 1 Dedicated Administrator Connection allowed. If the Dedicated Administrator Connection is already used, it will fail.
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