I bourght a new Acer Aspire E3-112. I use external screens both at home and at work. After installing Ubuntu everyting worked. I used it at home and at work. The second day when I got home the external screen was not to be found in the system. I was almost like it stopped working.

After a while I tried to install Xubuntu. After installing there was no external screen but after updating I could find it but I had to activate it in the screen settings. I then used it a few more days but now the hdmi is nowere to be found. I can even see it in the settings so that I can activate it.

It looks like the HDMI port has been switched off. I have serched the net but found no help.

I have new information. I got back to my office and then the hdmi port worked. So I think that this is what happens.

  1. I install Ubuntu with two monitors at home. My external is a 27 inch Panasonic. It starts to work after installing an updating. It will continue to work at home until I take it to the office and use my 21 inch LG monitor. It will continue to work at the office but I can't even see the port. I have attached an image where I have circled the hdmi port. In the office I can see the icon at home I can only see it after fresh install and update as long as I don't plug it in at the office.

I needed 10 reputation to post the pic.

2 Answers 2


I had a similar problem. I wiped Winows 10 and installed Ubuntu 14.04 and the HDMI output worked in that the laptop screen was mirrored to HDMI. So I could watch BBC iplayer for example. Then I upgraded to Ubuntu 16,04 and the only HDMI output was the ubuntu screen with no programs running . So I reinstalled Ubuntu 14.04 (clean install) and the only program that gets mirrored to HDMI is Skype. Not Firefox etc. I can no longer watch BBC iplayer on HDMI now.

Any ideas please?


That HDMI of E3-112 is "HDMI port with HDCP support" and which should be understood as "HDCP RESTRICTED" - High-Bandwidth Digital Content Protection, a copy protection scheme to eliminate the possibility of intercepting digital data midstream between the source to the display.

So at some moment the restriction has been activated, most probably by online or offline event. Think what it could be in that direction.

  • Last time I checked HDCP was only relevant to watching copyrighted BluRay discs. Feb 3, 2015 at 1:00

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