I did something weird so I can't find any thread that answered this. I used to connect to my PC (remote) from my Laptop by VNC. Today I was trying to set up Teamviewer. After I connected with TeamViewer, I realized it freezed. Now I am trying to connect with VNC. It can connect but it just shows the screen from that moment and clock and everything is for that moment. How can I force the server PC to refresh? Also, As I know, the Alt+Ctrl+Del doesn't work on ubuntu. Both side Ubuntu 19 with a display.