Gmail keeps going offline in Apple Mail

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!

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.

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

Big Mike posted a substantially similar question here a short time ago: Why Does Mail Keep Asking for a Password?

I have no idea what took two hours to solve, but if you are required to use Google then you might need to contact them: Contact a third-party vendor - Apple Support

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.

d18ge wrote:

UPDATE #3:

My hunch still says this is an Apple problem and there is probably an easy fix if someone would just look into it.

You could try raising the issue through Apple Feedback, they don't reply but at least you have tried to make them aware of the issue directly, include links to various discussions as well.

Product Feedback - Apple

If you all wouldn't mind going Feedback - macOS - Apple and report your issues so that Apple will get this fixed sooner rather than later? As of right now it is obviously just an inconvenience but who's to say it will not get worse.

Did you look in the private library the computer has?

1. Open finder
2. press and hold down the option key
3. then press go and scroll down about halfway to that library
4. then search for that file name.

Hopefully this helps.

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.