I had same issue when I upgraded to 7.11.1 email stopped working. Tried everything to fix but no luck. I ended up going back to 7.10.13 as 7.11 seemed a mess including Elastic Search which I donāt plan on using was giving a ton of errors in log and Google Calendar also isnāt important to me especially if Suitecrm calendar works fine.
I donāt know if 7.11.2 fixes these problems or not and donāt plan to upgrade anytime soon till I am 100% sure. A CRM without a functioning email is worthless. Suitecrm needs to get the basics working perfectly and not worry about adding advance stuff till then. Priority - Emails, email features, workflows/automation, calling features/reporting, better mapping, color coding of fields - just some suggestions.