After years of using Office for Mac 2011 and Outlook, I have decided to move to the free Apple Mail instead of forking out £229 for a single Outlook 2016 license.

With Outlook, I was able to put the "Microsoft User Data" folder any place I liked, then place a link on each drive where Outlook was going to look for that folder. So, each of my three operating systems were dealing with the same database.

Is there an equivalent approach to Mail? Where is the Mail database? Am I asking to something that Mail can't do?

Thanks.

If I understand you correctly, when you set up the IMAP accounts in Apple Mail on any and all devices, they will automatically be synchronized IF you have checked System Preferences>iCloud>Mail. What does not synchronize are any mailboxes you have created in Mail under the category of "On My Mac".

However, in re-reading your post, I notice you mention "my three operating systems", so I am wondering if you are trying to access Apple Mail "stuff" through a non-Apple system, or if you just mean different versions of Apple OS. If the latter, then my opening comments still apply. If the former, all bets are off.

Maybe a little more info unless I am missing the obvious.

It may be helpful if you tell us what data is stored in your Microsoft User Data folder so we can relate it back to the equivalent data in Mail.app.

I have three drives on the same Mac running 10.6.8, 10.10.5 and 10.13.2. I have a fourth HDD that has the Microsoft User Data folder on it. Each OS drive has a link where the User Data folder should be to the actual folder on the fourth HDD. This way, if I receive mail on 10.13.2, it will show up automatically when I reboot in 10.10.5.

I have mail set up now on all three partitions and my laptop. I have to say, Apple Mail does a good job of syncing the various computers. Who knew? Also, gmail is good over the various systems via the cloud, too.

My problem now, is saving the Microsoft archive of hundreds of emails so I can access them when my license no longer works.

Given the number of emails you are dealing with a stand-alone email archiver such as Email Archiver Pro, or Eagle Filer might be the best alternative for long term storage and access.

I'll look into those. Thanks.