Delete Extended Web Application in SharePoint 2010

  1. Start Central Administration

  2. Go to Application Management

  3. Select the Web Application from which the site(to be deleted) was extended from.

  4. Click Remove SharePoint from IIS Web Site (as shown above)

  5. Select the extension (zone) to be deleted

  6. Select Yes to delete the IIS Web site.

  7. Finally click OK and you are done !!

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