Help - Probes/OpManager

Good afternoon all,

I hope you can help I have a Windows 2012 box setup as a Central server and 2 CentOS 6.6 Boxes setup as a Probes.

When installing the Probes and entering the correct IP/Port in the correct format I keep getting "Probe Registration Failed" back on the CentOS box.

Wireshark on the Central server shows the HTTP GET and response, plus a TCP Dump on the Linux box shows communication is working. Basic communication such as Ping/Telnet are working so it would seem to be a fault with the Centos Box / Central Server.

Can you please advise some stuff I can check on both the Windows Central Server and CentOS Probes?

Looking forward to your responses,
Kind regards,
Ryan