Can't Connect to Vbox Virtual Machine on my Ubuntu server via windows RDP

Solution 1:

Had the same problem following the guide you used. Did the following to fix the problem:

enable multi-connection

sudo VBoxManage modifyvm ubuntu16 --vrdemulticon on

allow port 5001

sudo ufw allow 5001/tcp

reboot

sudo VBoxManage controlvm ubuntu16 savestate
sudo reboot
sudo VBoxManage startvm ubuntu16 --type headless

finally, can open Microsoft Remote Desktop to enter IP address and port

PC name: 192.107.123.12:5001

a screenshot of connecting to Remote Desktop

The above worked for me on a Ubuntu 18.04 server with Virtual Box 5.2.44. Think should also work on Ubuntu 16.04 with Virtual Box 6.1.

Hope it can be of any help!