I’m running MacOS 10.14.2 on my MacBook.
1. I set up iCloud, and under System Preferences –> iCloud I put a checkmark next to “Mail”.
2. I also put a checkmark next to “iCloud Drive”, then I click the “Options…” button, and in the new window I put a checkmark next to “Mail.app”
I don’t understand what’s the difference between checkmarking “Mail” in #1 vs. “Mail.app” in #2. What will happen if only #1 is checkmarked? What will happen if only #2 is checkmarked? What will happen if both #1 and #2 are checkmarked?
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Tom
So System Preferences, iCloud, Mail (#1) is for using your iCloud email account. This enables it on the computer and you'll get your email in the Mail app.
System Preferences, iCloud, iCloud Drive, Documents, Mail.app (#2) is for your Mail app preferences. If you look at the top of that list of options, you'll see it says "Apps that store documents and data in iCloud will appear here." So Mail doesn't really have any documents, but it does have a lot of data -- specifically the settings. So all of the preferences and settings in Mail.app will be synchronized across your devices.
This comes in very handy when you have non-iCloud email accounts. For instance, I have a Gmail account too, and because of this setting when I set up a new device and add iCloud, the new device is not only configured to get my iCloud email, but it gets the settings that contain the information about my Gmail account too. So I never have to set that up on the new device.
Many thanks Gary for your clear answer. It all makes sense now!
As an aside, I *do* have non-iCloud email accounts. I was afraid that if I checkmark #2, this would copy all my "Mail data" (i.e. the emails downloaded to my Mac from my non-iCloud accounts, which are handled by the Mail app) to iCloud, chewing up valuable iCloud space. Now I know this is not the case, and that what #2 does is actually very useful!
Thanka