Multiplayer fails to synchronize

[ソヴィエトの巫女]

 

Description

I am experiencing a multiplayer synchronization problem in SimRail.

When I join a multiplayer server as a driver, I can select a train, but the loading screen never finishes and the game remains stuck there.

When I join as a dispatcher, I can enter the station, but the game does not synchronize with the server. The in-game clock remains at 12:00, and no trains appear on the dispatcher panel.

The problem occurs on every multiplayer server I have tried, not just one particular server.

Singleplayer works normally.

Troubleshooting

I have tried the following:

• Restarted the router.
• Checked Windows Firewall and confirmed that SimRail is not being blocked.
• Verified the integrity of the game files through Steam.
• Reinstalled the DLC.
• Reinstalled the game.
• Temporarily disabled IPv6.
• Tested other multiplayer servers.

None of these changed the problem.

Network diagnostics

I can reach the SimRail server.

A traceroute reaches the destination network through my ISP(KDDI) and OVH infrastructure.

However, the SimRail log shows that the multiplayer connection is established initially, followed by a KCP timeout.

After the timeout, the client attempts to reconnect, but the same problem occurs again.

This appears to indicate that the initial connection/handshake succeeds, but the subsequent KCP communication does not remain synchronized.

conclusion

Makes me suspect a problem with multiplayer synchronization or KCP communication rather than a corrupted game installation.

I have attached the relevant log file for further investigation.

I am connecting from Japan, but it seems other users are able to connect.

Could you please check whether there is a known issue with multiplayer synchronization/KCP connections causing the client to remain at 12:00 or become stuck on the driver loading screen?

Thank you.

P.S. I accidentally posted in the wrong forum, so I have reposted this.

 

SimRail_log_2026-08-30_04-15-54.txt

[Admin BOT]

Thank you for reporting this issue. A similar problem has already been reported by other users.
Dziękujemy za zgłoszenie tego problemu. Podobny problem był już zgłaszany przez innych użytkowników.

[kojonek2]

Logs do not indicate any handshake from the server. We had some users with similar problem and it turned to be ISP issue (they blocked udp to whole OVH ip ranges). Try writing to them and asking to unblock port 7777 and 8888 with protoctol udp for simrail servers ip. For example int1: 5.135.168.248