Windows 7 and SharePoint 2010

If you are using Microsoft Office 2007 on Windows 7 against SharePoint then under certain circumstances there can be authentication issues which are highlighted everytime you open an Office document from SharePoint.  Circumstances you will see this are client machine has:

Windows 7 with Office 2007

Internet Explorer with no proxy settings

You use a Fully Qualified Domain Name for SharePoint (i.e. http://home.domain.com/)

To resolve this alter the registry following these steps:

1. Open the registry on the Windows 7 machine.
2. Navigate to: HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\WebClient\Parameters
3. Add a Multi String Value called 'AuthForwardServerList'
4. Add in your server addresses to the Multi String Value  http://home.domain.com/
5. Save and exit the registry and then restart the WebClient service

This will resolve these authentication issues.  If you do still get these then also check you have added you SharePoint FQDN to the trusted sites as this can also cause problems.