When you use a fully qualified domain name (FQDN) or a custom host header to visit a Microsoft SharePoint Server 2010 Web site or a Microsoft SharePoint Foundation 2010 Web site from the server that is hosting the Web site, you receive a Blank page.
Note You only receive a blank page if you try to visit the Web site directly from the server. If you visit the Web site from a client computer, you can view the Web site.
This problem occurs when the Web site uses Windows Integrated Authentication and the Web site has a name that is mapped to the local loop back address.
To work around this problem, disable the loop back check or specify host names.