Block All Users Except the Site Collection Administrators

[Frederick Wilson]

I would like to shutdown a site collection to all users but the Site Collection administrators. Currently I used the PowerShell cmdlet to lock the site but now the site collection administrators cannot get to the site.

[#2]

If you can do it via gui just assign yourself to the site collection admin and go to advanced site permissions and you should be able to just remove all users and groups. ThAt will remove everyone except site collection admins.

Or do you need to do this through PS only?