After install docker, problems with running

 You may need after installing docker execute permissions to all users that execute docker, the commands are:

• $ sudo usermod -aG docker $USER
• $ sudo systemctl restart docker
• (close terminal or restart machine)

Then docker will run without using sudo.

Problems with Virtualbox Guest Additions

Before installing Virtual Box Guest Additions you may need install some software to not having problems with screen or resolution or even worst kernel damage, the commands are the following:

• $ sudo apt-get update
• $ sudo apt-get install build-essential dkms
• $ sudo apt-get install linux-headers-$(uname -r)

Best Regards,

GOOGLE ERROR 400