Virtually all of my photo albums are on my SD card. I get this error message everytime I try to move an image from (for example) the Screenshots Folder to any SD folder. Your answer didn't help. First, I believe you are actually referring to Apps -> Samsung Cloud -> App Info, NOT Apps-> Settings -> Samsung Cloud which I can't find. Second, in neither the location, do I see a solution.
I have opened this question in the Chrome browser & will search for other possible solutions, but if the only answer is to not backup my Gallery, then of what use is Samsung Cloud?
This is especially true given it presumably won't be a backup solution if I ever move away from Samsung. I plan to do this in the coming months because Samsung phones continue to experience slow-power-charging & other serious charging errors on its Note 8 cell phone, replacement phones have the same problems, & Samsung will take your phone for 2 weeks but not first ship you a loaner! Who can live without their smartphone for at least 2 weeks knowing if Samsung chooses to replace it, some or all of your data from your old phone will not be transferred to your new one? What kind of "warranty" is that?