Forum Discussion
Mac Mail - Outlook Exchange issues
Well, for whatever its worth it just went back to working again. Not sure if it was a Microsoft issue or an Apple issue but Exchange account/Mac Mail - Catalina is working just fine again.
The same thing has happened with all of our office computers. We picked the most reliable product (Apple) and the most reliable office apps (MS Office) for our business so it eludes me that in 2021 these issues occur and they are not being addressed. Apple and MS - Hello out there.... there are tens of thousands of businesses that have bought into your products. Let's get on this!
We're having this problem too... all Mail app users on Office 365. If you launch Console on any of the Macs having this problem, search for "subscription" and you might see "EWSStreamingSubscription" logs with error "EWSErrorMessage=You have exceeded the available subscriptions for your account. Remove unnecessary subscriptions and try your request again". What we've seen so far might be related to EWS throttling mentioned https://docs.microsoft.com/en-us/exchange/client-developer/exchange-web-services/ews-throttling-in-exchange?redirectedfrom=MSDN. Microsoft modified/removed the limit for us temporarily last year but it re-enabled in the new year. When our server team reached out to them again, Microsoft said they no longer had the ability to set it, and despite escalating it to their enterprise support, we reached a dead end. Pretty much we were advised to use Outlook or reach out to Apple support. Here's the last/closing email from Microsoft:
"As a quick recap and conclusion mentioned by my TL, Microsoft is not controlling this, we cannot make changes regarding this and in order to move forward with this issue you would need to engage Apple support and see if they can change the EWS subscription limit on their native mail client or reduce the TTL of subscription request."
"Microsoft cannot change the EWS subscription limit or reduce the TTL of those subscription request for Apple. Apple has to change those since it is using their native mail client app. It is not configurable for EXO, please reach out to Apple regarding this specific query."
Right on! Thats pretty interesting. I'm more of a front end guy than back end server stuff but I think I'm following along. If MS isn't going to control/limit the EWS pings/connections then on the Apple side, an over abundance of those coming in could get blocked until everything is cleared/reset. Is that the gist? If I have the issue again in the future (over three months with no issues now) then I'll certainly pop open console to look for this message. Question would be, is there a user based fix, maybe through Activity Monitor or Terminal to clear out the subscriptions to get a fresh set up? THANKS!
Correct. I don't know how to clear/reset things on the client side but Apple Enterprise Support suggested decreasing the frequency of mail checking from Automatic to maybe every minute or 5 minutes to see if that would help avoid reaching the subscription limit. Aside from that, they offered no other troubleshooting steps aside from working with their cross platform support team that could work with Microsoft support. That is my next step. As a possible workaround if the user doesn't want to move to Outlook, you could enable IMAP for the email sync and then Exchange to sync contacts and calendar, but leave email syncing off. We did this for one user just to get her by.
