When trying to set the AnonymousPermMask64 property via SharePoint 2013 Management Shell, I get a "Access is denied. (Exception from HRESULT: 0x80070005 (E_ACCESSDENIED))" error on line 3 of the following command lines:

1 $web = Get-SPWeb http://sps2013/
2 $web.AnonymousPermMask64
3 $web.AnonymousState = [Microsoft.SharePoint.SPWeb+WebAnonymousState]::Enabled
4 $web.AnonymousPermMask64 = "ViewListItems, ViewVersions, ViewFormPages, Open, ViewPages, UseClientIntegration"
5 $web.update()

I am logged into the server as the domain/administrator account and running PS as Administrator from the Start menu. This is SP2013, Windows 2008 R2, SQL Server 2012 on Oracle VirtualBox.

I am trying to enable anonymous access to a Site Collection - the public landing page. I enabled anonymous access from CA, but the page still prompts for a user name/password. Clicking [Cancel] several times results in a partially rendered page. I think this is a result of the list items not being truly anonymously accessible.