We have had MSN e-mail accounts for 20 years. Recently the e-mails stopped appearing on the mac e-mail icon. I think Microsoft made some changes a while ago that I didn't adjust to.
Mac mini (M4)
FWIW. MSN email has gone through many variations since it initially evolved from HoTMail in 1997. Today Microsoft provides Outlook.com to users as their primary free email service.
You may find the following reference an interesting read: https://www.webopedia.com/definitions/hotmail/
However, if you try to add an Outlook.com account to the macOS Mail app, you will not find it listed as one of the predefined accounts. What you would find is "Microsoft Exchange" ... which is not what you would want. Instead, you will need to select "Add Other Account," and then, enter the appropriate email server information.
Since most of us do not know what those could be, Apple provides you with this website where all you need to do is enter your (in this case) your MSN email account's email address: Mail Settings Lookup
I just did this with a facticious MSN email address, named: bob.smith@msn.com and it provided all of the information you will need to use to fill in the "Add Other Account" asks for. Of course, you will want to use your MSN email address for this.
Ref: Add email accounts in Mail on Mac - Apple Support
FWIW. MSN email has gone through many variations since it initially evolved from HoTMail in 1997. Today Microsoft provides Outlook.com to users as their primary free email service.
You may find the following reference an interesting read: https://www.webopedia.com/definitions/hotmail/
However, if you try to add an Outlook.com account to the macOS Mail app, you will not find it listed as one of the predefined accounts. What you would find is "Microsoft Exchange" ... which is not what you would want. Instead, you will need to select "Add Other Account," and then, enter the appropriate email server information.
Since most of us do not know what those could be, Apple provides you with this website where all you need to do is enter your (in this case) your MSN email account's email address: Mail Settings Lookup
I just did this with a facticious MSN email address, named: bob.smith@msn.com and it provided all of the information you will need to use to fill in the "Add Other Account" asks for. Of course, you will want to use your MSN email address for this.
Ref: Add email accounts in Mail on Mac - Apple Support
Try Microsoft’s Outlook App - works good, can recommend.
My microsoft e-mail account no longer comes up on my mac icon
