A template uses the alias &1. The alias exists, but is not referred by any link in the Site Structure.
&1 - The Alias ID read from the template.
The alias &1 has been used in a template (in a /(MENU-...) replacement marker) - a corresponding entry has been read from the alias table - but no link refers this alias in the site structure.
Another possibility is that the alias has been specified on an external link (deep linking). If this is the case, a message of the type EvF149 will be written to the message log after this one.
Either change the alias in the template or specify the alias for a link in the site structure (using the "Menu Service" button).