Running into this using UNC paths.
VisualCron runs on one server. Jobs are set up to execute a EXE on another server.
That destination server was recently upgraded from Win Server 2003 to Win Server 2012.
Immediatelly after a reboot of our Visual Cron server everything works. Eventually however VC thinks the server on which the programs reside is no longer connected (maybe it does at one point). However, when we get the error I can verify that there is an active an available connection to execute the EXE per the UNC path. But Visual Cron will not do it.