Sierra Mail does not sync with my Exchange server anymore.

Hi Mynet,

thank you very much for your solution, which finally worked out for me!

However, I had to delete the account and wait for some time (~30 min.) until I could re-add it, because Mail on Sierra was causing my Account to fall into quarantine each time I opened the program, which may have caused my OWA issue.

Internal URL (in my case) https://ews.example.com/EWS/Exchange.asmx

External URL (in my case) https://email.example.com/EWS/Exchange.asmx

Which I find particularly interesting is that my Internal and External URLs were both valid and exactly the same in all my previous non-functioning account installations. The only difference is that I did not enter them manually before.

Thank you very much again.

Best regards,

Clemens

After following your advice everything works fine now. Many thanks!

Yeah, great reply. Works before Sierra, doesn't work after Sierra. Must be someone else's fault to fix other than Apple's.

The IOS devices use the EAS protocol, while your MAC uses EWS, so they can give different results

Happysam wrote:

Yeah, great reply. Works before Sierra, doesn't work after Sierra. Must be someone else's fault to fix other than Apple's.

What's your problem.

It's Working. Thank you for your support.

Hi Clemens,

Many thanks, your solution worked for me.

By the way in my case the problem appeared when I changed the option to store the drafts on the server.

Without that everything worked fine so far...

This is very strange...

Well I lost a few hours, but thanks to you everything works now...

Rgds

Hello All,

I've finally found the issue in my case: Mac is using EWS, and a rule exists in Exchange server that prevents EWS connection when there is a server overload risk. I don't know the exact details, but with this protocol there is limitation when an account is using too much server ressources, and when the server detect this situation it closes EWS for this account.

Typical symptom is server answering "ErrorServerBusy"

https://social.msdn.microsoft.com/Forums/office/en-US/340ee405-64f4-4d01-8eb6-54 4cb6fb1b8b/why-am-i-getting-exchangewebservices-inbox-error-error-errorserverbus y-the-server-cannot-service?forum=exchangesvrdevelopment

I suspect that when I upgraded to Sierra, something went wrong and mail overloaded the server.

My IT resolved the problem by resetting something on the server and now, everything works fine.

Cyril

Same issue here. Sending/receiving mail through the Exchange server was fine, but the calendar was not updating at all after the Sierra update. After reading the suggestions from others, I deleted the exchange account on my Mac, and then added it back, after which Mail and the calendar synched up just fine.

I have the same issue even though I use Mynet's solution. After close and reopen Mail.app, it still fails on receiving new mails but sending mails.

Reference About the macOS Sierra 10.12.1 update - Apple Support, does this patch help this issue?

From my part, it doesn't have any progress on this issue.

Is there any suggestion?

Thanks

Edgar

Hi,

MacOS Sierra update to 10.12.1 from yesterday solved the issue for me. I had to remove / re-add the account after applying the update.

Hi ptouron,

Thanks for your information, but I already update my MacOS to 10.12.1 and still suffer this issue after remove then re-add the account.

Also, I remove all stuff below ~/Library/Mail/ before re-adding my Exchange account, this issue still happened.

I've tried to use Mail.app with a Guest user, this issue still can be reproduced.

I have no idea how to solve it...

Hi,

The issue I encounter is related to how mail.app handle EWS operations for an Exchange 2010 account (no issues for my two others Exchange (cloud) accounts whatsoever). I can send mails, change items indicators (read, unread, flag, ...) and it syncs properly, but mail doesn't refresh folders on synchronization. I have to reopen the app to sync properly (even connection reset doesn't do the trick).

I checked server-side and I managed to see sync requests goes by without issue. I wanted to check logs client-side, but they are empty. I spoke to AppleCare Outreach about the issue, but they cannot give me a feedback. It was 2 or 3 weeks for now and I didn't took the time to open a case. If you have the same issue, it's not yours to solve.

That being said, I spoke a bit too fast this morning; I saw that the update would solve an Exchange connection issue in mail.app and immediatly applied it yesterday, then recreated the faulty account (didn't worked before) and it worked again as intended ! But since I rebooted (yes, rebooted, because of a non related issue) my MBA this morning, the issue came back. I don't have time right now to test everything on different configuration, recreate again the account and so on... I'll try asap and write back here if I find something.

Hope it helps to pinpoint the issue.

This problem persists for me even after it was reportedly fixed in 10.12.1 a couple of days ago.

Symptoms are the same:

- Auth works fine on starting up mail.app, fetches all new mail, then nothing

- Sending e-mails works just fine on same exchange account

- Re-entering exchange account with tweek posted in this thread did nothing for me

Hi,

Thank you for spending time report your status.

I created a test user and did some dirty test.

I just found if I reply a mail sent by myself faster than Mail.app sync with Exchange server, then it could work without this issue.

But the issue will come back after you re-open Mail.app.

So...still missing a solution now.

I'll post something If I have any update.

Cheers

Edgar