Setting Options In Alert!:

Alert! has several options that let you tailor its operation to your needs. To set these options, use the Options button in the Alert! window.

The Diagnose option has two radio buttons that allow you to decide whether or not to include volumes other than the startup volume in the search for problems. It’s possible to include either the startup volume only, or all locally mounted volumes. Remote volumes mounted on your Macintosh from another machine across a network will not be scanned.  Use the Alert! Network Responder  to do this. Choosing to search all volumes will lengthen the search if you have several mounted volumes.