Probe registration problem

Hi,
I am using Opmanager MSP 6003 with license for 25 probes. I have 24 Probes configured and working fine. When I tried to install the 25th probe it would not start. It just gets stuck on "Verifying communication with web server".
I checked the wrapper.log and shows "waiting for registration from the central server".
I tried running registerprobe.bat and to the following:

C:\Program Files\AdventNet\ME\Probe\bin>registerprobe.bat
Error in receiving data Connection refused: connect
Error in receiving data connect: Address is invalid on local machine, or port is not valid on remote machine
Error message got while registering = This copy of ManageEngine OpManager supports a maximum of 25 probes only. To increase the limit / for further details please contact AdventNet.
The Probe was not registered with the Central Server. The Central Server may be
down or some problem with registering. For further details refer the previous log messages in this console or Central Server logs.

Please help.

Thanks
Gus