Export emails but keep them searchable I've got a couple of mailboxes for old businesses on my MacMail. I keep them there because there are loads of emails, and I may need them in the future. The reason I haven't just exported them and archived them is that I still want them to show up in search results when I search through my emails.
The problems I have are:

I keep getting notifications that I have to put the passwords in for these mailboxes. That's very frustrating.
For some reason, something keeps blocking my IP address from one of the business' domain name. Any time I log onto a different wifi, it blocks that IP address too. I suspect it's something to do with invalid details on one of these mailboxes (but if it could be anything else, please let me know).

My ideal solution would be to have these mailboxes sat there, but completely inactive, not connected to the internet in anyway, just a repository for a bunch of emails. But I may have to face facts that I may need to delete them altogether, exporting the emails first. But then they won't be included in the search. Is there any way I can have my cake and eat it?
You can move the emails to a 'mailbox' which is only on your Mac.   The instructions here assume you have the latest version of macOS and Apple Mail, but older versions are much the same.

In Mail's sidebar on the left you should see &quot;On My Mac&quot;. With the
mouse, hover, click on the disclosure triangle to show the mailboxes
(folders) inside &quot;On My Mac&quot;.

Create a new mailbox (folder) by clicking on the + symbol.  You may
want to create multiple mailboxes to keep your emails organised. You
can even create a tree structure if you want.

Then just drag and drop (with the Command key pressed) your old
business emails from the external mailboxes into your new mailboxes
within &quot;On My Mac&quot;. The command key ensures that you do a copy (not a
move) as you probably don't yet want to delete them from the external
service.

Alternatively use 'Copy to' from the Message menu.

You can now disconnect from the old mail services.


The emails will be indexed (it will take a little) and be available to Mail's search.
Because the emails are now stored just on your Mac, you become responsible for ensuring your backups are sound.