I've been mounting a scenery with App-V on HyperV and Windows Server 2008... but as I were installing I got this error:

"Error 25120. The installation program was unable to create the required IIS Virtual Directory”

So it seems we have to install the IIS 6 Metabase Compatibility, IIS 6 Management Console and IIS Management Scripts and Tools in order to be able to install.. so by following the next steps, you should get the work done.

To install the IIS 6.0 Management Compatibility Components by using the Windows Server 2008 Server Manager

1. Click Start, click Administrative Tools and then Server Manager.

2. In the left navigation pane, expand Roles, and then right-click Web Server (IIS) and select Add Role Services.

3. On the Select Role Services pane, scroll down to Management Tools and select IIS Management Scripts and Tools, then scroll down again to IIS 6 Management Compatibility.

4. Select the check boxes for IIS 6 Metabase Compatibility and IIS 6 Management Console.

5. Click Next from the Select Role Services pane, and then click Install at the Confirm Installations Selections pane.

6. Click Close to leave the Add Role Services wizard.

 

But after this, when I got to the management console, I couldn't connect, I kept having this Error 0000C801. But again, I solved this issue by installing the Role of Windows Authentication in IIS7.