I'm trying to add a new (joint) e mail account both my wife and I can use. Having trouble. How do I do this? I use Mac Mail.

When you have an email account and want to be able to check messages from multiple devices, the account should be set up as an IMAP account, which is the default these days. Then multiple devices and or accounts can access the emails, and everything is tracked properly. Once read from ANY device, a new email will be marked as read by EVERY device.

What you are asking for is perfectly ordinary, just a few more Readers than typical.

I do not know why the directions posted online are ALWAYS fossils, from a previous geological era.

what is the Service Provider?

Jack-Z wrote:

Thanks but I know that already. I just want to add/use an additional e mail address and can’t seem to remember how. Thanks

Are you and your spouse using separate devices? Or separate user accounts? Or something else?

If you're using separate devices or separate user accounts, all you need to do is add the account to both devices or both accounts.

Add email accounts in Mail on Mac - Apple Support

System preferences > Internet accounts ...

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Hi Jack-Z,

thanks for reaching out in the Apple Official Community.

Are you trying to use Apple iCloud's Custom Email Domain function or are you trying to simply add an email that both you and your wife can use?

Best,

Matteo