One of our Drupal servers lost connection to where our ubercart files are located (see below)

File download settings
The absolute path (or relative to Drupal root) where files used for file downloads are located. For security reasons, it is recommended to choose a path outside the web root.

and then within all of our users "File downloads" section (https://domanname/user/21/purchased-files) it lost all of their listing of purchased files and also all the ubercart products lost their association to attached Feature/File download files.  It appears that shortly after a Drupal server loses connection to where the ubercart files are located it then deletes all the associations to ubercart Feature/File download files and also all the users "File downloads" sections are empty.

How do I prevent this from happening when one of the drupal servers has lost the connection to the product files directory?

Thanks,

John