Error 'Server not found' during installation of Enterprise Console 4 on Windows Small Business Server 2008

Issue
During a custom installation of Enterprise Console 4 on Windows Small Business Server 2008, you enter the details of a server (and, optionally, an account to use for updating) and then click Next. You see one of the following error messages:

List is empty

Server not found. Verify that the specified server exists.

Known to apply to the following Sophos product and version
Enterprise Console 4

Operating system
Windows Small Business Server 2008

What to do

The domain controller cannot be contacted because network discovery is not switched on by default on the Small Business Server. To continue with the installation, you must turn Network Discovery on and reboot the server:

1. On the Windows Small Business Server 2008 desktop, right-click the Network icon and select Properties.
2. In the Network and Sharing Center, under 'Sharing and Discovery', select 'Turn on Network Discovery'.
3. Reboot the server and then start the installation program again.