There's a slight issue with Remote Access Only VERDE installs.  For example, VMWare with VERDEOS, Virtual Box with VERDEOS.  

When a user attempts to login and access the Target PC, the issue manifest itself in the following error:

Simply access the Management Console/Configuration/Computer Resources.  The MAXIMUM NUMBER OF SESSIONS field is probably set to zero (0).  Simply edit the field (press the EDIT button) and increate the value to something greater than 0.  50 is sufficient.