Can't change desktop background when using separate spaces on monitors?

[Sharky II]

Hi,

Not strictly a Mac Pro problem, but I do have 2 graphics cards, each running a screen, and I have 'Displays have separate spaces' selected in Mission Control.

Every time I change my desktop background (on either screen), when I restart the computer, the backgrounds have reverted to the El Capitan 2 (blue) background.

I've tried trashing Finder prefs, to no avail.

Anyone able to offer a solution?

Cheers!

Ed

 

[flat five]

are the images custom pictures or are they the stock ones included with the OS?
if you're trying to use custom images, try using one of the alternative stock images instead to see if that helps?

also, for a custom pic as the desktop, it's simpler to just right-click on the image file then choose 'Set Desktop Picture' instead of going into system preferences..
so try that too to see if anything changes?

I've tried trashing Finder prefs, to no avail.

hmm.. i think you'd be wanting to reset the Desktop prefs.. not finder.
however, it's not like the good ol days when you just trash a .plist to reset it to defaults.. macOS (and some OS X) has backup .plists now so they can regenerate in the user library when one goes missing.. you'll likely need to resort to terminal in order to reset the preferences to default value. (and i don't know the exact commands/files off hand so you'll have to search the web for it.. it's going to be something like defaults delete com.apple.desktop)
[doublepost=1492566022][/doublepost]also, one pretty good method that's maybe more steps than necessary to see if a case such as this is because of your hardware or something like a corrupt .plist would be to try doing the same thing in a different user account.

create an account which will have a fresh desktop .plist then set the new desktop images.. do they stick now upon reboot?
if so, your account's .plist will need reset.. if not, then yeah, probably something to do with having a GPU per screen in which case, i have no ideas.

 

[mattspace]

IIRC the desktop background is a part of the Dock process, so that might be a direction to have a look.