After upgrading to Windows 10 on my main work computer, I could no longer connect to 2 XenServer 6.2 hosts and found out that the error was “Could not create SSL/TLS Secure Channel”. After a bit of lazy searching I found a forum post that fixed the problem.
The actual fix for this is as follows.
service xapissl stop
mv /etc/xensource/xapi-ssl.pem /etc/xensource/xapi-ssl.pem.bak
/opt/xensource/libexec/generate_ssl_cert "/etc/xensource/xapi-ssl.pem" '10.10.6.27'
service xapissl start
Replace the 10.10.6.27 with the IP of the server host you are attempting to fix. This should resolve your ability to connect from XenCenter.