[SOLVED] Need Help Connecting With a Friend Over The Internet: MHFU

[Kennethern]

I'm not entirely sure what I'm doing wrong here. I've done everything short of installing a VPN service, such as Tunngle or Hamachi, to set up a private ad-hoc server. My friend and I can join the guild hall in MHFU, see each other's characters as well as randies, interact with each other and even accept quests being started by each other. When we attempt to start, though, the game takes around 60 seconds to load and when it does it states that "[Insert Hunter Name] Broke Off From The Group!"
As of now, we've tried all of the below to fix the problem.

• Enable Firewall Inbound/Outbound Rules Allowing PPSSPP Through
• Using The Built In PRO Ad-Hoc Server w/ Port Forwarding
• Using An External PRO Ad-Hoc Server w/ Port Forwarding
• Disabling Windows Firewall All Together
• Disabling The "Fast Memory" Setting
• Trying Multiple Online Ad-Hoc Servers Such As Coldbird.net and Coolbird.net
• EDIT: We've tried using Hamachi and Tunngle as of now, to no avail.
  

Any help would be greatly appreciated.

Solution: Currently, re-installing my Windows OS seems to have fixed the problem while connecting to Tunngle, but not much else. I would recommend using Tunngle over any other vpn service for PPSSPP multiplayer.

[tywald]

Joining the GH is the easy part, to not break off when quest starts is the hard part.

Who is hosting the quest? Try let the other do it and if it works, then you know who's having issues.
You might have 3rd party software like McAfee, AVG, Avira, Avast Premier etc. that can block as well, go through those if you have any.
Go over PPSSPP settings, activating hacks like "Timer hack" etc. can also break you off. Fast memory being turned off is for making 3-4 players work(it should be off at all times anyway, no need to have it on).

[Kennethern]

I'm honestly not sure what the problem actually was, but I just reinstalled Windows 10, "refreshed" it with a backup image of my previous OS and now it works with Tunngle, using the exact same setup as before, but not with anything else. Thank you for your help.