Transfer mail data from one Mac to another .
- Take back up of all mails in V 7 folder
Click on finder take cursor on top menu bar > Go and hold option key click on > library > select mail folder > right click on mail folder there itself > click on copy mail > right click on the desktop > click on paste item .
Entire mails are copied to V 7 folder and will get saved on the desktop .
Note : For Mac OS mojave the folder will be V6 , For Mac OS High Sierra the folder will be V5 , For Mac OS Sierra the folder will be V4 , For El Capitan - the folder will be V3 , and for OSX Yosemite the folder will be V2 .
Take a USB flash drive and copy V7 folder into it , once it is copied right click on the USB flash drive and eject it .
Insert the USB flash drive in the second machine .
Configure new IMAP account ( the mail address should be say example2@icloud.com ) in another machine and take cursor to the top menu bar , file > import mail boxes > import data from > select apple mail > click on continue > select the back drop folder then choose new .
When new IMAP account is opened a new folder with all mails will appear in the mail side bar , you can rename the folder .
Note :
( a) And if you plan to switch gmail to iCloud or even change the internet servicer provider the folder " import " is still saved in the empty mail application , the mails will start syncing .