WSSAdmin
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The term "WSSAdmin" is short form for Windows® SharePoint™ Services Administrator.
When you first signed up for your Windows SharePoint Services account you were assigned a user which was named something like WSSAdmin@your-domain.com where your-domain.com is your actual domain name. Please note that this is not an email address and does not have any email functionality. This is simply your first SharePoint user which has Administrative and Collection Administration rights for your Windows SharePoint Services site.
This WSSAdmin user can be used to log in to your SharePoint site and assign permissions to other users of the site. For information on how to add additional users to your SharePoint site, you can refer to the article entitled "How can I add additional users to my SharePoint™ Services site?"
