Strange iCloud notification

[md4peace]

On restarting my computer this morning (Mac Pro OS 10.9.5), I got this message:

"Sorry, iCloud Drive isn't compatible with OS X Mavericks.

You've upgraded your account to iCloud Drive. To keep your documents current across all your devices, update to OS X Yosemite.

Tip: Documents stored in iCloud Drive are always available at iCloud.com"

It seems to think OS X Yosemite is available.

 

[NoBoMac]

Yosemite is not available. Looks like the generic error message.

Guessing you loaded iOS 8 to a device and enabled iCloud drive either via setup, Settings, or using one of the iWork apps.