I'm having a tough time with my remote gateway setup. I've been able to configure remote gateway farms on Server 2019 and 2022 without issue before, but now I'm facing a problem. I built a simple remote gateway with a Network Load Balancer, but it took around 30 seconds to establish a connection. So, I rolled back the NLB and went through various troubleshooting steps, eventually ending with just one remote gateway on a fresh install. I tested both Windows Server 2025 and 2022 and ran into the same problem with a minimal setup.
I'm not using the standard port 443; let's say I'm using port 444 for this. I've tried altering RAP and CAP policies, checked port conversions, and looked into any issues with CRLs, but nothing has worked. The weird thing is that everything runs smoothly on MacOS, Linux, and mobile clients, but when I attempt to connect with different Windows 11 devices, I get an error (0x3000008) almost immediately. I even tried creating a Windows VM and experienced the same issue. I confirmed that the mobile device on the same network could connect without any issues.
Every time my Windows clients try connecting, they do reach the RDG network because I see packet counts rising. I'm at a loss here after multiple setups and configurations. Has anyone else run into this before? I feel like I might be overlooking something really simple. Thanks in advance!
2 Answers
Yeah, Windows clients always start with UDP and might have a fallback to TCP. You can confirm if that's the case by disabling UDP. Just keep in mind, even with your setup on port 444, Windows will still try to switch to UDP first. If things are still a mess after that, it could be that your router is blocking UDP traffic somewhere along the line. But then, it’s strange because your other setups work fine, right?
I think the issue might be related to how Windows Remote Desktop works. Windows will by default try to use UDP, while many third-party clients stick to TCP. If your Windows clients are failing, maybe try to disable UDP to see if that helps your connection problem. You can do this by going into the registry at HKLMSOFTWAREPoliciesMicrosoftWindows NTTerminal ServicesClient and setting DisableUDPTransport to 1.
Thanks for the tips! I'm going to check those settings to see if it helps. It's strange that the fresh install has the same issue though. I'll try disabling UDP and see what happens. Appreciate it!