Hi - I recently noticed this problem after installing the latest August 2012 CU. The Edit Properties and Rename Page options are greyed out on pages that I try to edit. I am a site admin and a site collection admin.
This is the message I get:
Unable to display this Web Part. To troubleshoot the problem, open this Web page in a Microsoft SharePoint Foundation-compatible HTML editor such as Microsoft SharePoint Designer. If the problem persists, contact your Web server administrator.
Any ideas? thanks