Hi Mike,
Are you sure you didn’t use Chimera syntax, which has the color before the spec? That is the common reason for this error.

Your command looks fine, and works for me when I try it in daily build (2/19) and 0.8 release (12/17/2018).

However, the simpler approach for element N is just to use element symbol:

color N blue

Also if you don’t want to also color the ribbons entirely blue (all amino acids have N), you may want to add that target is atoms:

color N blue target a
 - or -
color N blue atoms

I hope this helps,
Elaine
-----
Elaine C. Meng, Ph.D.
UCSF Chimera(X) team
Department of Pharmaceutical Chemistry
University of California, San Francisco

> On Feb 17, 2019, at 1:17 PM, Michael Lawrence <mikeclawrence@gmail.com> wrote:
>
> Hi, I am trying to use wild cards in chimerax but they appear not to work. I type the command
>
> color @N* blue
>
> and get as response
> Expected a color or one of 'byatom', 'bychain', 'byelement', 'byhetero', 'bymodel', 'bynucleotide', 'bypolymer', 'fromatoms', or 'random' or a keyword
>
> All I am trying to do is color all nitrogens blue.
> Version 0.5 (2018-02-05) running on macOS Sierra v10.12.6
>
> what am I doing wrong?
>
> thanks
>
> Mike Lawrence