Restore Sharepoint Site Use Sharepoint Powershell

• Run Sharepoint 2010 Products -> Sharepoint 2010 Central Administrator -> Application management -> Manage Web Application click New

• And then fill name of website, port, register account for website click OK.
• Run Sharepoint 2010 Products -> Sharepoint 2010 Management Shell, write script :

Stsadm –o restore –url -filename <”(location and name of file).bak”>

•  
• Check Collection administrator

Run Sharepoint 2010 Products -> Sharepoint 2010 Central Administrator -> Application Management -> Change site collection administrators -> use username is administrator

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Courtesy:http://tedyseptiady.wordpress.com/2011/01/07/restore-sharepoint-site-use-sharepoint-powershell/