Gmail keeps going offline in Apple Mail

Sure no problem d18ge.

FINAL UPDATE: After doing alxxhrvth's 4 steps a couple of days ago (as I posted about a few replies ago), I still ended up getting the offline indicator for 5 of the 6 gmail accounts that I re-added to Mac Mail. It would happen after Mail.app was hidden for approximately 2 or more hours. So, why not the 6th gmail account? That question I had gave me an idea. Well, if you go to the menu bar in Mail-->Accounts you can adjust 4 checkboxes for each gmail account. They are Mail, Contacts, Calendars and Notes (M, Co, Ca, N). When you setup a gmail account it defaults with all 4 checked. That is probably why alxxhrvth's 4 step program works for the majority. Because it makes us setup an account back to default. But, some of us uncheck the boxes right away. When I was doing alxxhrvth's 4th step the other day, I had left one of the 6 gmail accounts, let's name it Eureka@gmail.com, with the dafault 4 boxes checked. On the other 5, I had unchecked the Co, Ca, N so that only Mail was checked. Yesterday, I checked my inbox and Eureka@gmail didn't have an offline indicator and the other 5 did. So, I messed with the 4 checkboxes on 4 of the 5 troubled gmail accounts. I did different combinations of checkboxes and then I let it run for the last 24 hours. Today, when I went to my inbox after it hiding for more than a couple of hours, they were all online except the one that I left with only mail checked. It didn't seem to matter if I checked M and N, or M and Ca, or M, N, and Ca. Just as long as M (obviously) and one of the other 4 boxes is checked.

CONCLUSION: Make sure that another of the four boxes besides Mail is checked in Mail-->Accounts-->youremail@gmail.com

I called Apple support, quickly exhausted solutions offered by first level support, and was transferred to senior level support.

The issue was finally tracked to malware that setup a SOCKS proxy. In network settings, advanced, proxies, there should have been no proxy. The tech suggested Malwarebytes to scan, identify and remove any malware. It worked like a charm!

I have no idea where I picked it up. As a network engineer in a previous life, I am wise to most all phishing schemes!

Just check calendars (apart from mail) in by going to internet accounts and it should work. I had unchecked all except mail and it had stopped working. You can either check all again (waste if you only use other email accounts just for mail) or just check calendar and mail.

Thanks

POSSIBLE FIX!

So today I got really annoyed by this, again... So I called Apple support and I think they might of helped to me get rid of this.

Here's what I did:

1 Remove all Gmail accounts from Mail

2 Add a new network location and then renew the DHCP lease

3 Delete "com.apple.mail-shared" in Library/Preferences/

4 Restart and add my Gmail accounts

I can't really tell which of these is the actual fix, but I'm now 7h later and did not experienced this at all. Fingers crossed!

Sometimes, the easiest solution is to delete the problematic email account(s) and add them again. Add or remove email accounts in Mail on Mac - Apple Support provides those instructions.

However, I don't use Google either, so I wouldn't know what Google's "critical security" problem could be, or if it's related to what you describe.

I remember seeing another post describing a similar issue if the Mail App was minimised or kept in the background, this appeared to follow the last update.

I believe to keep Gmail "connected" he discovered putting Mail into it's own "Spaces" seemed to work, switched between his working desktop and Mail's every time he wanted to check his messages was quicker and less frustrating than continually closing and re-opening.

It's obviously no fix but might be worth trying.

I don't use Gmail but do have two other accounts in Mail, an ISP POP account and iCloud. Following the update the SMTP server for both went off-line and stayed that way even if the Mail App was restarted.

Strangely this issue was limited to the SMTP side, POP and IMAP remained unaffected.

In the end I just deleted and re-added the ISP account at the same time turning off and then on again iCloud, which appeared to sort the issue out.

I suspect (but this is just my guess) that the update had somehow got the accounts using the wrong smtp servers so they could never actually connect, who knows, all a bit of a mess and shouldn't really happen.

I have been having the same issue ever since I updated to the latest macOS (10.14.4). Currently Apple is reviewing all different types of logs to see why this is happening. But, it looks to be a macOS bug rather than a google problem.

Update to my previous post:

I turned off the check boxes for Gmail's Contacts, Calendars and Notes but it started to squawk again so I turned just Gmail Notes back on and it immediately calmed down.

A few days later I turned Gmail Notes off (bc having the feature on adds GMail in the Notes App and I didn't want or need it). Luckily, there have been no further Gmail offline issues. Even though it worked I don't think what I did was a proper fix.

Did you look in the hidden ~Library folder? That com.apple.mail-shared file is in the Library that pops up when you press the Option key while looking in the "Go" menu of Finder.app.

UPDATE: Most of the day the fix worked for me. I did catch it once after it was hidden for a few hours, where all 6 of my gmail accounts were offline. So, the 4 step approach is an improvement but still needs some work for me.

Well done! When I set up my new MacBook I unchecked all the boxes except Mail because I noticed checking Calendar put a LOT of extra "empty" calendars on view when I use the Calendar app. I just checked ONLY the "contacts" box for all my accounts and when I opened Mail, all the little "offline" symbols one by one disappeared! YAY!

I'm glad we (really Y'all) figured this out, but I can't help thinking this is still something Apple should fix.

I just checked and have checked for the past week for an OS update! Still Nothing!

The problem extends to not only Gmail accounts, but other mail accounts in eluding iCloud Mail! It affects calendars too!

From what I've been experiencing, it also seems to affect browser sessions in Safari! Application Wifi connectivity in general!

It's been a matter of WEEKS now from the point the Mojave 10.14.4 update had been released, and STILL NO FIX from Apple!

Apple broke it, Apple needs to fix it ASAP at this point!

12 hour Update:

No offline indicators to report this morning when unhiding Mail.app. I failed to mention yesterday regarding my final interaction with the settings on the 6th gmail account, I toggled the Mail checkbox off and back on again. Then I added 2 more checkboxes for a total of 3.

Through this gmail troubleshooting session the last few days, there have been two icloud accounts in my Mail.app that have been behaving normally.

Now that you mention it, that timeline seems about right snider.m. That 10.14.4 update is about when I started noticing the offline indicators in Mail.app. It didn't start to annoy though for a couple of weeks after that.