Possible reason for this error is if spacedeskService stopped running or you accidentally switched OFF the spacedesk server via menu button.
Could you please check the following:
- can you find the spacedesk tray icon on your primary machine's task bar's notification area?
- please click the spacedesk tray icon to open the spacedesk server (user interface) window and check the spacedesk server status, is it OFF/ON/ERROR?
- in case you cannot find the spacedesk tray icon, could you please run "services.msc" and find spacedeskService and if it is currently stopped, just right-click -> Start it.
For further analysis, please send us further details of your setup:
- primary machine's graphics adapter, network type (wired/wireless)
- spacedesk viewer type (windows/android/iOS/html5)
- secondary machine network type (wired/wireless/USB tethering)
Could you also please update to our most recent spacedesk Driver version 0.9.17.
Looking forward to your feedback.