When setting up a virtual service recording session it is not possible to select the VSE as it does not appear in the dropdown list.
Recordings have previously worked.
In the vse.log, notices are seen that the service cannot be created in the directory vsBuilderSessions/<VSE_NAME>_<VSE_PORT> where VSE_NAME and VSE_PORT reference the VSE that cannot be selected. An example of the directory name is vsBuilderSessions/VSE_2013
This is applicable to all current versions and is not OS dependent
Previous recording session files in the appropriate directory under vsBuilderSession are corrupt or incomplete. When scanning these files the error parsing them prevents the VSE from being reported as available to process further recordings. This folder is used by the virtualisation API, and thus the portal.