Getting a Folder Name is Not Valid error when trying to open a server based site?
Problem:
In Expression Web (version 1 or 2) or FrontPage you click File/ Open Site, then type in the http:// address of the site.
This is a common operation for making quick changes to a live site or to open a server based site to publish it back to your local computer.
After the site opens for you in the open web dialog, you can see the folders, but when you click Open, you get an error saying "The folder name is not valid".
Solution:
Just double click any folder inside the site you're trying to open and the parent site will open for you.
