On IE version 11.0 running on Win8.1 I can successfully log in to http://www.performanceconsultants.com/wp-login.php. I land on my Account page http://www.performanceconsultants.com/account-2 and can see the membership I have signed up to (we're using Membership 2 Pro). The black admin bar appears at the top of the page with 'How are you, [my.username]?' showing. As soon as I move to any page on the site (protected or otherwise) the black admin bar disappears and protected content is restricted. So, I have clearly been logged out.
The trouble in not occurring on Chrome version 43.0 running on Win8.1. The black admin bar remains and protected content is available.
I have granted Support Staff Access in case needed.
Thank you for your help.