The server could not complete your request SharePoint designer 2010

Here is a common problem often faced while opening a SharePoint Site in SharePoint Designer 2010:”the server could not complete your request SharePoint designer 2010”. If you click the Details button it will open a dialog box; however, it is almost always empty..

If you are face this problem, check the Event viewer for the following error: “The extended protection settings on IIS do not match the settings configured on the transport”. If this error appears, follow the steps below:

• Open IIS Manager (Click Run in start menu and then type INETMGR)
• Find the desired site in IIS Manager
• Open “Authentication” from body panel
• Select Windows Authentication
• Click “Advance Settings…” in the right panel
• Select “Off” from the extended protection dropdown box
• Select the check box for Enable Kernel-Mode authentication
• Click Ok.
• Reset your IIS

You are done. eNjoy...