using ultravnc latest stable, windows xp, all updated, comodo cis all updated and current and for the life of me (this install only) never had this issue before
I can hit my vnc with the firewall disabled but not with it set and the the rule for the executeable to allow both incoming and outgoing all ports which has fully worked before.

I’ve deleted and put the rule back same thing

firewall off vnc works great, firewall on its blocked.
its puzzling me.