Hm. I just tried it out and it seems you are right. The Designer only displays Bound columns. I'm really not sure why that is. There's no reason why you should be able to use an Unbound column as your ValueMember or DisplayMember. Might be a bug in the designer. 

You can, of course, just type in the name of the column you want, or set it at run-time. 

I am spoiled in the designer by having all the possible values to choose from.  The unbound columns do not show up, but I can type it in.

So is it a bug if all the choices do not show in the designer?

Hi Mike, 

What's the problem? Why can't you choose an unbound column? The UltraCombo really makes no distinction between the two. And setting the DisplayMember is just a string. So what's stopping you from choosing an unbound column? 

I know it's been a long time since this was closed but I struggling with this now.

It only lets me choose from the columns in the bindingsource.  I can't choose an unbound column for the DisplayMember.

Am I missing something?

Mike,

Thanks for your clear answer, as usual a nice one!