Template VMs won't run terminal

I am having a strange problem.

I want to update my Whonix Template VMs. However, I cannot get them to launch a terminal window. The icon bounces around for about 30 seconds then dies without anything happening. This affects all my Whonix VMs (template and proxy) but affects none of my non-Whonix VMs–they open the terminal window promptly.

Other packages besides terminal open and run correctly in Whonix VMs.

Advice?

This issue:

  1. start xterm
Qubes VM Manager -> right click on VM -> Run command in VM -> xterm
  1. install locales-all
sudo apt-get install locales-all

Thanks. It worked.