Hi @thyagueau,
Could you please try to uninstall the spacedesk in your primary machine using the „msi installer -> Remove“ or using the Windows Control Panel, then reboot your primary machine, and reinstall it.
If the above suggestion did not help, and you still have the failed installation error, please send us the following:
– run dxdiag.exe on your primary machine, click „Save all information“ and send us the output file
– spacedeskSetup.log file located in C:\Users\Public
– setupapi.dev.log file located in C:\Windows\INF
Please save all requested files in one folder, then right-click -> Send to -> Compressed (zipped) folder, then attach the *.zip file in your next reply.