Click OK to close the error dialog box. You may need to click it several times.
Error: "Operation can't be completed" adding files to Creative Cloud | Mac
Error "The operation can't be completed" when adding files to Creative Cloud storage using Finder shortcut
When you try to add files to the Creative Cloud file storage by dragging them onto the Creative Cloud folder shortcut in the Favorites section of Finder, you receive an error "The operation can't be completed."
Solution: Close Creative Cloud and relaunch Finder
Close the Creative Cloud desktop app. Depending on your version of the Creative Cloud desktop app, do one of the following:
Relaunch Finder by right-clicking the Finder icon in the Dock while holding down the Option key. Choose Relaunch.
After relaunching Finder, the issue no longer occurs. Adobe apologizes for any inconvenience in relation to the error. Our engineering group is aware of the issue, and plans to address it in a future update.
If you continue to face difficulties uploading files, consider using an alternate method such as opening and placing them directly in the Creative Cloud Files folder.