Trouble starting RMServer after upgrading to 8.10

I "upgraded" from RM Server 8.00 (free edition) to 8.10.  The server service starts, and then quickly quits.  I tried a full installation next, deleting the previous server directory, files, and service.  Same result.  The server service starts, the CPU utilization is pegged at 100% for several minutes, and then the service quits.  Next I tried creating a new schema and another full installation.  Same result.  I killed the service after several minutes of 100% CPU utilization, and that appeared to fail as well.  Service shows as Stopped in Windows Service list, but CPU still pegged at 100%.  I had to restart to clear the condition.  Any help would be greatly appreciated!!