When I protect a content page with Public Access in Umbraco 4.7.1.1, then try to view the page on the front-end, (not as a logged in member), I would expect to be redirect to a login page, instead I get the following error:

The username of a Member must be different from an emptry string

Wondering if anyone else is experiencing this?  From investigating the core changesets, the code change was introduced in v4.7.1.1.

Full stack-trace:

[ArgumentException: The username of a Member must be different from an emptry string
Parameter name: loginName]
   umbraco.cms.businesslogic.member.Member.GetMemberFromLoginName(String loginName) +407
   umbraco.providers.members.UmbracoMembershipProvider.GetUser(String username, Boolean userIsOnline) in c:\Program Files (x86)\teamcity\buildAgent\work\b1348deba90dacc5\umbraco\providers\members\MembersMembershipProvider.cs:581
   System.Web.Security.Membership.GetUser(String username, Boolean userIsOnline) +63
   umbraco.requestHandler..ctor(XmlDocument umbracoContent, String url) +4587
   umbraco.UmbracoDefault.Page_PreInit(Object sender, EventArgs e) +1062
   System.Web.Util.CalliHelper.EventArgFunctionCaller(IntPtr fp, Object o, Object t, EventArgs e) +14
   System.Web.Util.CalliEventHandlerDelegateProxy.Callback(Object sender, EventArgs e) +35
   System.EventHandler.Invoke(Object sender, EventArgs e) +0
   System.Web.UI.Page.OnPreInit(EventArgs e) +9009622
   System.Web.UI.Page.PerformPreInit() +31
   System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint) +328

I've searched around the forum and CodePlex, but nada.

Cheers, Lee.