Missing emails past around 3 months

I’m not sure why or what has happened but all emails from older than 3 months to the day are just gone from all IMAP. I need to keep all emails forever. How can I make sure we are keeping mail not purging it when that is not what we want to do?

I use Thunderbird.
My buddy uses Outlook.
My other buddy uses Android.

The results are the same across all devices.

Mail-in-a-Box does not purge emails.

Some email clients however can be set to do so.

Without knowing more about your MiaB install there is really no way to help you.

Did you update to Ubuntu 18.04 and not restore a backup perhaps? This is doubtful as you would have noticed long before today.

Have you checked that emails aren’t being filtered and moved to a different folder that is not subscribed to by your client?

It would be highly unusual for mail to just be ‘gone’.

I started on 18.04. I was thinking since this was across all the accounts I can see maybe it was a server setting to archive things or purge them…

When I look on the roundcube settings I don’t see anything about auto-archive.
I don’t see any in the iphone mail.
Looking at the Thunderbird settings everything looks normal I have no auto archive settings. I have it set to “don’t delete any messages” and “synchronize all messages locally regardless of age”

Very strange … if you go into Roundcube settings Folders, are there any unsubscribed folders there?

All are subscribed. And I took another look at the other settings just to be sure I don’t even see any archive options in roundcube.

If you SSH into your server and look at the actual maildir files … are there none older than 90 days there? Take a look at a mailbox for one or two users and see.

sudo su
cd /home/user-data/mail/mailboxes/host.yourdomain.tld/user/cur
ls -l | less