If monitors are powered down, can't get a connection

  • In our school's computer lab the the monitors will go into power save mode. When this happens, I can see the computers in Veyon Master but when I try to take control all I see is a black screen and the remote connection won't work, it just gets stuck with a black screen.

    It would really help if, when a remote control is started, for Veyon to wake up the monitor so the remote session works. Kids bring their own keyboards and mice to class (for covid), so it is a pain to wake up the monitors manually when there are no mice or keyboards attached.

    I don't know if this makes any difference, there is only one monitor but it is plugged into a Quadro p1000 graphics card and not the intel integrated graphics port, maybe with the monitor off the Veyon client is choosing the incorrect display device?

    Thanks for any advice!


  • @mayers

    This can be done with PowerShell.

    Create the batch file wakemon.bat with the commands below.

    = = = = = = = = = = = = = = = = = = = = = = = =

    powershell -NoProfile -NoLogo -Command "(Add-Type '[DllImport("user32.dll")]public static extern int SendMessage(int hWnd, int hMsg, int wParam, int lParam);' -Name a -Pas)::SendMessage(-1,0x0112,0xF170,-1)"

    powershell -NoProfile -NoLogo -Command "$x=Add-Type '[DllImport("kernel32.dll")]public static extern void SetThreadExecutionState(uint esFlags);' -name System -namespace Win32 -passThru; $x::SetThreadExecutionState([uint32]"0x03"); Sleep 5; $x::SetThreadExecutionState([uint32]"0x40");"

    = = = = = = = = = = = = = = = = = = = = = = = =

    Copy wakemon.bat to each computer's C:\Windows folder.

    Use Veyon's 'Run program' feature to wake the monitors of your selected computers by entering C:\Windows\wakemon.bat.

  • @itguy

    You could instead copy the wakemon.bat file to a shared network folder then use 'Run program' to run the batch file from the shared folder: