virtualbox.org

VirtualBox Graphifcal User Interface Version 5.2.18 Ubuntu
Host System: Ubuntu 18.04.2 LTS
Guest System: Windows 10

Hello,
I turn the computer on and boot into ubuntu.
Then I launch virtualbox and the vm with win10.
Then I insert the USB-device. It is an EV3 from Lego.
It is never shown in the bottom right corner where I can pick a USB device.

A simple solution is shut down the VM. Close Virtualbox and log in ubuntu again. Usually it works then.

But it is really annoying and time wasting. Is there a solution for this?

Thanks you very much.

Please provide a VM log file. With the VM fully shut down, right click it in the GUI. Select "Show Log" and save "VBox.log" (no other file) to a zip file. Attach the zip here.

Here is the log-file in a zip.

VirtualBox VM 5.2.18_Ubuntu r123745 linux.amd64 (Dec 27 2018 00:41:57) release log

As I suspected, you are not using VirtualBox at all. An obvious side effect is that you are also not using the VirtualBox plugin which provides USB 2/3 support. If you want to use Ubuntu's fork of VirtualBox then that's fine, but there will be no support for it here.

If you want support here then you need to install the real thing, not the tribute band clone: https://www.virtualbox.org/wiki/Linux_Downloads. Note the instructions for adding offical VirtualBox packages to your package manager list.