overcome issue with starting 4K plug and play unit with Windows 10
I note others have issues with the software update for your DisplayLink device as I do but, annoying as it is, there is a workaround that I have to use.
Start your computer, (Mines a Dell Lattitude 3440), and add password to the Windows 10 start screen that appears on the laptop.
The mouse and keyboard connected to the DisplayLink work so you can use them to go to "Restart" and restart your computer.
Most times it will then migrate the screen image to my IPS LED screen.
(The Windows 10 function key system to change monitors does not do this though it did before the latest update of DisplayLink software)