PFDAVadmin error: Could not expand http://(mailbox folders) on Windows 7

When you try to open your Public folders or User mailboxes with PFDVAdmin on your Windows 7 client, you receive the following error:

Could not expand http://(your mailbox folders)

In my case, this problem occurs in combination with Exchange 2007.

Resolution

- First, install .NET Framework 1.1. It can be downloaded here. Now retry to open the public folders or user mailboxes.

-  If this still is not working, be sure you are using an account which is an Exchange administrator.

- You can also try to open PFDAVAdmin with secondary logon with an Exchange admin account. The steps can be found here: