MacOS – Disable Notification for specific Account in Messages

I've been using AIM since the "AOL days" and I can say without a doubt that the AIM servers have always been unreliable. More so once we started using it via iChat and iChatAV and now Messages.

There are two (maybe more) reasons that I know of for AIM dropping out:

1. The part of their service that checks your login credentials (username and password) goes down.

2. The part of their service that allows clients other than the AOL web client to connect goes down.

I've never been able to figure out where the problem is and at this point there are so many other more reliable ways to connect via Messages that I'm not all that worried about it.

That said, many of my oldest buddies remain on AIM because that was the first system that Apple used with iChat, then iChatAV so it's important to keep that connection alive until we can all migrate to .me or google or something else that Messages supports and is more reliable.

There is an option within the preferences of Mail.app.

Go to the "Accounts" tab, and select the email account, and under Account Information, you can set the outgoing mail server to None.

You must also enable Use only this server.

When sending a message from that account, you will now get a message asking you to choose a different outgoing mail server, with the option of cancelling the send.