Can't duplicate swatches

[Bob Cal]

Hi,
Suddenly, at some point over the past couple of days, I cannot duplicate swatches using the color palettes drop down menu item "Duplicate Swatch".

No message, just doesn't do anything. I've updated Illustrator and my machine (Windows 10) to very latest. But this issue is baffling. Plenty of workarounds to do that, but I never realized just how often I use that step in my daily work until it went away. So would be great if someone has a solution for fixing that. 
Best,

Bob

[Monika Gause]

What kind of swatch is it?

When was the last time you rebooted the computer?

[Bob Cal]

Hi Monika,
It's an RGB global swatch in an RGB document. 
I've updated both program and computer, so today alone I've rebooted numerous times. 
Have you encountered this before?

[Monika Gause]

Have no issues duplicating that kind of swatch. Did you also reset the preferences? This will erase your settings.

[Bob Cal]

Thanks for testing it out. I was worried I'd have to go through the trouble of doing that. Weighing the plus and minuses of that. Again thank you, kindly.
. 

[Monika Gause]

You can quit Illustrator and then rename the preferences folder. It will make a new one. And if it fails, you still have the old folder

[Bob Cal]

Thanks again, Monika!