Discovery and Risk Assessment Server 2013 - "Empty path name is not legal" error

You may receive the following error when attempting to save a Discovery file in Discovery and Risk Assessment Server 2013:

 

 

Error saving Discovery settings. Empty path name is not legal.

The error may occur when you click "Discover" in the Discovery window:

 

 

When starting a Discovery, you are prompted with the following dialog box:

 

 

If you click on Yes, you see the error instead of getting a dialog box to allow you to save your changes. This can happen if you do not have a Discovery file configured in the Discovery settings.

To resolve the error,  go to File > Save As and save the Discovery configuration as a .dis file before running or closing the Discovery configuration window. Then go to File > Configuration in the main Discovery menu and select the .dis file in the Discovery File text box:

 

 

You will need to restart Discovery for the change to take effect.