Drag and drop problem

What kind of files are you trying to drag to iCloud Drive? You must not drag Photos Libraries there, as they will be damaged by the syncing, and you cannot keep items on iCloud Drive, that are larger than 50GB.

See: Access and manage files in your iCloud Drive - Apple Support

You can store files* in iCloud Drive as long as they're 50GB or less in size and you don't exceed your iCloud storage limit. If you need more iCloud storage, you can buy more. If you choose a 200GB or 2TB plan, you can share iCloud storage with your family, without sharing your files. Learn more about prices in your region.

*Avoid storing app folders, libraries, .tmp, .vmdk, .vmware, .vbox, .vm, and .pvm files in iCloud Drive.

lilly_papa Said:

"Drag and drop problem: Simple yet annoying: Can't drag and drop files from my Mac to my iCloud drive. Nothing happens when I try it. Why??"

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Three Things to Try:

A. Have a VPN Enabled?:

If so, disable it, as there is a misconfiguration.

B. New iCloud Session:

Log out of iCloud, and then log back in. Perhaps it all needs to resync.

and...



C. Try Safe Mode:

Boot into Safe Mode [Hold Down: the shift key upon boot], wait 30 seconds, and then restart normally. In Safe Mode, damaged system fires (i.e. caches) are intensionally fixed.