I am following the Blender fundamentals tutorial from the official Blender site. When I try to select the 3 cubes and do Ctrl+P, I get this error.

In fact I get that error even if I shut down Blender, restart and press Ctrl+P with just the basic cube after the startup and having done nothing else. Weirdly, after that selecting the objects doesn't work, pressing A to deselect starts the animation player. X doesn't work and a number of such things. This happens even after I reset to factory settings.

Also when I parent by setting the parent in the Object properties window it works without any issues.

I am running blender downloaded from the official site and installed in Ubuntu 18.04.

What is the problem? What can I do to fix this?

  • $\begingroup$ Hi, welcome to the site! What error are you getting? Also, screenshots aren't required, but they are always helpful so we can see what's going on. (: $\endgroup$
    – SilverWolf
    Commented Oct 27, 2018 at 20:56
  • $\begingroup$ And which version of Blender are you using? $\endgroup$
    – SilverWolf
    Commented Oct 27, 2018 at 20:57
  • 1
    $\begingroup$ Mate, it looks like keyboard problem - check if Alt did not get stuck (stay pressed)! The shortcut for playing the anim is Alt + A and also Alt + X wiil do nothing in fact... $\endgroup$
    – Jan Matys
    Commented Oct 27, 2018 at 23:39
  • $\begingroup$ @JanM Even if this wasn't the answer for the op (I think it is very likely though), you should add this as an answer. It could be helpful for other users in the future. $\endgroup$
    – Leander
    Commented Oct 28, 2018 at 7:33
  • $\begingroup$ ... very very likely since ctrl-alt-P also gives proxy error message. $\endgroup$
    – batFINGER
    Commented Oct 28, 2018 at 17:16

1 Answer 1


According to the commencts I decided to put the answer like this.

In situations where some shortcuts does not work like they should and restart of a program does not help then try to search for stuck keys (keys stayed pressed).

The question above looks like a keyboard problem (ALT key) and sometimes its really hard to find out!

Sincerely, Jan

  • $\begingroup$ I am providing some context. I am using Blender 2.79b. I've got Ubuntu installed on a Macbook Pro. For convenience I had mapped Control onto the Command keys. That was the problem. For some reason pressing Command generates both Ctrl and Alt key presses. All other applications ignore the Alt, but it seems Blender picked up both and kept the Alt sticky, even though it wasn't pressed. Clearing the keyboard mappings resolved the error. I think this is a minor bug in how Blender/Python process keyboard inputs. $\endgroup$
    – gautam
    Commented Nov 3, 2018 at 9:26

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .