Ok, thanks for the help here. Definitely would be lost without it. I’ve documented it as best I can here in case this helps someone else.
So successfully installed/re-installed the packages as above, into the cli/php.ini . fpm/php.ini and apache/php.ini (just to be safe) as I said above. And I had restarted Apache, but restarted it myself.
But when I tried " php -i | grep php.ini " I received a laundry list of errors from these new extensions which essentially said “HP Warning: PHP Startup: Unable to load dynamic library…” for most of the newly added extensions. So that means I have a path issue (or possibly a permissions issue).
And then when I created a “phpinfo()” page it now says I’m running php7.1, not 7.3 (which wasn’t true at the beginning of this process, so I must have screwed something up/back to php7.1 in my desperate flailings). But php -v and php -i show php7.3. So I fixed this with a2dismod and a2enmod and now phpinfo() and
php -i both show 7.3 properly.
So, without fixing the errors “HP Warning: PHP Startup: Unable to load dynamic library…” for most of the new extensions, the SuiteCRM error “Inbound Email cannot function without the IMAP c-client libraries enabled/compiled with the PHP module” has now disappeared.
So is all good? Let’s check first. I successfully set up a personal email and see my emails in the inbox (and it let me select the inbox, sent and trash folders). So that’s good.
And I successfully sent an outgoing (from SuiteCRM) test email from this account and received it no problems (and said it was from the correct account). So that’s good.
But my first “user generated” email sent (outgoing from SuiteCRM user login) as a test failed, and said “Error Sending Email. Please contact your administrator for assistance.” and the SuiteCRM log said " [FATAL] SugarPHPMailer encountered an error: SMTP Error: Could not authenticate. " which is strange since how did the user test email correctly get sent from the user account if the user can’t authenticate?
It looks like this is a more common issue:
So to summarize: thank you for your help: I am now able to configure incoming emails, although I couldn’t say specifically which of these changes fixed the issue. And now I have more work to do on getting user emails out. But I’ll struggle with this for a few more days and see if I can get it working.