The license has reached GRACED state, as shown by
[root@pcs ~]# vzlicview status="GRACED" expiration="12/11/2013 06:59:59"
On the other hand,
prlsrvctl tool incorrectly shows the state as EXPIRED:
[root@pcs ~]# prlsrvctl info --license status="EXPIRED" expiration="12/11/2013 06:59:59"
No VM can be started:
[root@pcs ~]# prlctl start testvm Starting the VM... Failed to start the VM: This product was activated for a trial period that has now expired. Purchase a new activation key to continue using Parallels Server.
Containers are able to start:
[root@pcs ~]# vzctl start 102 Container is mounted Starting the Container ...
The issue is recognized as a PCS product bug with internal ID PSBM-24018.
The issue will be fixed in the future product updates.
For now, it's required to update the license to allow VM start again.