DisplayLink was working just fine with Ubuntu 16.04, D3100, and two monitors (in addition to the laptop display). I upgraded to the latest DL a few months ago, but I forget what version that was. Last evening, I upgraded to Ubuntu 17.10 and experienced the "Ubuntu login loop." I uninstalled DL, and was then able to log in via lightdm. Next, I downloaded and installed DL 4.1.9, but my two monitors are always black.
I've tried unplugging monitors and docking station and plugging them back in. I tried unplugging docking station, rebooting Ubuntu, logging in, waiting a minute or so, and plugging docking station back in. None of this worked. Any idea how to get it working again?
UPDATE: I guess I haven't restarted my PC since I installed the latest DL when I first posted this two days ago. I just restarted it, and it turns out that I get the
"Ubuntu login loop" with the new one, too. This is what happens: I no longer have the two external monitors plugged into the D3100. Instead, I have just one of them plugged into the (lone) HDMI port on my laptop. Has been working okay like that. I restarted, get the Ubuntu login screen, I enter my password, the screen goes blank, then I get the login screen again. This is different than the bad-password screen. The fix is to uninstall DL. I miss that third monitor.
br,
Paul