Parsec Shows Error 6023 on a Vodafone Mobile Connection in Germany

August 7, 2026 3 answers
Asked by MellowBirch42
My friend and I want to play local co-op games remotely through Parsec. It worked normally while he was living in Hungary, but since moving to Germany and switching to Vodafone internet through a SIM card in his router, Parsec fails with error 6023. We have tried disabling the Windows Firewall and enabling UPnP on the router. Could the issue be that his connection is behind CGNAT and needs a public IPv4 address, or is there another setting we should check?

Answers

QuietComet18
Parsec depends on peer-to-peer connectivity, and it can become slow or fail completely when neither side can receive forwarded connections. If getting a public IP isnโ€™t possible, try a virtual LAN tool such as Hamachi or another game-networking alternative. It may work even when the router connection is behind CGNAT.

MellowBirch42: That makes sense. Weโ€™ll check whether Vodafone can provide a public IPv4 address first, then try a virtual LAN option if they canโ€™t.

Reply to this answer
CedarFox63
I wouldnโ€™t leave the Windows Firewall disabled as a troubleshooting solution. Turn it back on and create an exception for Parsec instead. Also check whether the router actually supports UPnP over the mobile connection, since enabling the setting wonโ€™t help if the providerโ€™s network blocks incoming connections.
Reply to this answer
OrbitingPanda7
This is probably a connectivity problem caused by CGNAT. Mobile and SIM-based internet commonly puts customers behind a shared public IP, so incoming peer-to-peer connections and port forwarding wonโ€™t work. Ask Vodafone whether they can provide a real public IPv4 address. Another option is a VPN that supports port forwarding, such as AirVPN or Proton VPN, although a regular VPN like NordVPN usually wonโ€™t solve this.
Reply to this answer

Add your answer

Answers are reviewed before publication.

Related Discussions