Comentário oficial
@I Beale > You answered your own question:
"i can only get the tracks to load if i disable firewall"
If the link works when the firewall is disabled, but NOT when it's enabled, the problem is the firewall.
See this article and read the "You can't get your players to link" section, where I specifically note "You need to configure this each and every time you install a new version of rekordbox."