You receive an error message when you try open a subweb that is using unique permissions in FrontPage 2000 Server Extensions from Microsoft (272542)

SYMPTOMS

When you open a subweb that is using unique permissions, the following symptoms occur:

You receive the following error message:
The folder 'http://servername/subwebname' isn't accessible. The folder may be located on an unavailable volume or protected with a password.
To confirm the problem, click Start, click Run, and then type frontpg http://servername/subwebname in the Open box. In this example, servername is the name of your server, and subwebname is the name of the subweb that you are trying to open. You see two instances of FrontPage running (one with the root web and one with the subweb), and the default document of the subweb in Notepad.
The following symptom occurs when you have the root web open and you double-click the subweb. When you try to save a page in the subweb, you are redirected to the root web in the Save dialog box. If you double-click on your subweb again, you receive the following error message:
The current operation cannot be completed because an unexpected error has occurred. For details see c:\TEMP\wecerr.txt.

In the Wecerr.txt file, you see:
Server error: The folder that would hold URL 'subwebname' does not exist on the server.

To resolve this problem, follow these steps:

Start the Microsoft Management Console for Microsoft Internet Information Server.
Right-click the virtual server that is experiencing the problem.
Click Tasks and then click Check Server Extensions.
When you are prompted to tighten security as much as possible, click Yes.