How to: Change the Service Startup Account for SQL Server (SQL Server Configuration Manager)
Use the SQL Server Configuration Manager to change the start up options of SQL Server services and to change the service accounts that are used by the SQL Server Database Engine, SQL Server Agent, SQL Server Browser, SQL Server Analysis Services, and SQL Server Integration Services. For more information about how to select an appropriate service account, see Setting Up Windows Service Accounts.
When you change the service startup account for the Database Engine and SQL Server Agent, the SQL Server service (the Database Engine) must be restarted for the change to take effect. For more information, see Additional Considerations for Changing SQL Server 2008 Service Accounts below. When the service is restarted, all databases associated with that instance of SQL Server will be unavailable until the service successfully restarts. If you have to change the service startup account of SQL Server or SQL Server Agent, make sure that you do so during regularly scheduled maintenance or when the databases can be taken offline without interrupting daily operations.
To change the SQL Server service startup account
On the Start menu, point to All Programs, point to Microsoft SQL Server 2008 R2, point to Configuration Tools, and then click SQL Server Configuration Manager.
In SQL Server Configuration Manager, click SQL Server Services.
In the details pane, right-click the name of the SQL Server instance for which you want to change the service startup account, and then click Properties.
In the SQL Server <instancename> Properties dialog box, click the Log On tab, and select a Log on as account type.
After selecting the new service startup account, click OK.
A message box asks whether you want to restart the SQL Server service.
Click Yes, and then close SQL Server Configuration Manager.
Additional Considerations for Changing SQL Server 2008 Service Accounts
SQL Server 2008 running on Windows Server 2003 and Windows XP
Changing the service account that is used by SQL Server or the SQL Server Agent requires SQL Server Configuration Manager to perform the following steps:
Stop SQL Server if it is running.
Restart SQL Server in single-user mode.
Connect to SQL Server.
Provision the new service account for the service (add the new service login) as a member of the sysadmin fixed server role.
Disable the old service account login inside SQL Server.
Disconnect from SQL Server.
Stop SQL Server.
Restart SQL Server in normal user mode.
SQL Server 2008 running on Windows Vista and Windows Server 2008 Stand-Alone Server
The above steps (service start/stop in single-user mode and connecting to SQL Server) are not performed when changing the service account that is used by SQL Server or SQL Server Agent when SQL Server 2008 is running on Windows Vista or Windows Server 2008. This is because SQL Server and SQL Server Agent service SIDs are provisioned as a login and as a member of the sysadmin fixed server role during SQL Server 2008 installation and the service account change has no impact on the per service SID.
Changing the service account that is used by SQL Server or SQL Server Agent must be performed from the active node of the SQL Server cluster.
When running on Windows Server 2003 and Windows Server 2008 (in a non-default configuration using Domain groups), changing the service account that is used by SQL Server or SQL Server Agent requires SQL Server Configuration Manager to stop SQL Server for the steps previously described above by taking the resource groups offline.
SQL Server 2008 running on a domain controller
If SQL Server services are configured using service SIDs, then changing the account used by the services does not require additional changes in SQL Server. If the SQL Server services are configured using domain accounts, then the service must be stopped to perform steps (a) though (h) listed above.
SKU Upgrade (SQL Server Express to non-Express SKU)
During SQL Server Express installation, the SQL Server Agent service is configured to use the Network Service account but disabled. SQL Server Configuration Manager can change the account assigned for the SQL Server Agent service but the service cannot be enabled or started. After SKU upgrade from SQL Server Express to non-Express, the SQL Server Agent service is not automatically enabled, but can be enabled when needed by using the SQL Server Configuration Manager and changing the service start mode to Manual or Automatic. For more information, see SQL Server Express Features.