If you try to log in to the SharePoint web application (http://site.company.com) using host header on the server itself, your windows credential don’t work but you can access the same site from outside.
The problem happens when you create a SharePoint web application with a host header (site.company.com) on the SharePoint Server (Server Name: company.com) which is installed on Windows Server 2008. This is a known issue with SharePoint 2007 or SharePoint 2010 on the Windows Server 2008 platform and this problem is happening even with the recent patches.
Solution at
http://www.mssharepointtips.com/tip.asp?id=1109[
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