Hi @nightmare-maxwell,
1. Do you VPN enable? If yes, please disable it.
2. Do you have third party firewall or antivirus software on your machine? If yes, please make sure to include spacedeskService (C:\Windows\system32\spacedeskService.exe) in the exception list to allow incoming and outgoing connection.
3. If you are connecting over WiFi network, please check if your WiFi router settings has client/WiFi/AP isolation enabled. If this is enabled, it will prevent direct communication between connected devices/computers.
4. Please also make sure your current network profile is set to Private, via Windows Settings -> Network & Internet.
For more info please check the Troubleshooting -> Network Connection chapter in the user manual https://forum.spacedesk.netuser-manual/.
If the suggestions above did not help, could you please send us the diagnostic info in your primary machine.
Just open the spacedesk Driver Console -> Diagnostics, then click the “Save All Information”.
PS: Saving all information will take a few seconds, then please send us the whole folder which contains all the diagnostic logs collected.
Please right-click the folder -> Send to -> Compressed (zipped) folder, then attach the *.zip file in your next reply.