Unable to subscribe to Office 365 IMAP folders from MUA since 2022-11-01

It's working for my accounts now.

Good news is this morning we found out that the issue got solved without notice.

We received a message a week ago about Microsoft Support saying they would start to see progress in around 15 days, but the solution came much faster.

Haven't received yet a confirmation email by them, but the folders seem to work fine in all the users affected and in all tenants.

Same here - looking pretty positive then. I've asked Microsoft 1st line on my ticket what the issue was.

I copied my message to the 1st line engineer's first line of escalation as I have done previously, and I've just noticed that individual's Display Name came up with (Shanghai Wicresoft) appended to it, so it looks like Microsoft have outsourced/off-shored O365 1st line to a third party - Wicresoft International. That might explain why there feels to be something of a barrier between 1st line and Microsoft Product Group.

O365 is accredited to hold data at UK "OFFICIAL" classification, so for Microsoft to be using a third party in China to do "support", it seems reasonable to assume that Wicresoft have little (if any) access to core Microsoft services and platforms and are just there as filter to protect Microsoft and deal with the easy queries.

Just had a reply. All 1st line seem to have been told is a fix was deployed and I think we'd got that far by ourselves.

Regarding another IMAP related incident recently affecting at least hundreds of tenants (IPv6 problems which I know some of you encountered too), I was advised I had to raise a Microsoft Premier Support case if I wanted a root cause providing for that incident. I fully expect to be told the same in this case if I try and escalate the lack of satisfactory feedback.

But this is starting to make sense. A Premier Support case will likely bypass Wicresoft's 1st line and be responded to by Microsoft support people.

Ours is a non-profit tenant, and even though the lack of feedback is intensely annoying on something I think should have been posted up on Service Health as an advisory anyway, I'm not about to waste charity money on Premier Support cases unless I really have to.

On a different matter, I notice Microsoft are reporting an incident this morning that has made the national press in the UK, and (see below) it's nice to see this HAS made it on Service Health :) They seem to be indicating some sort of network problem.

I got a phone call on monday 23rd acknowledging that they are working on a fix but witout ETA, then got another call at the end of the week that the fix has been rolled out. I asked our affected yours for feedback and got feedback that the issue has been addressed on their end as well. I worked with Microsoft support to confirm the issue with subscribing wasn't just a Thunderbird-specific issue by using the PopImap PowerShell to subscribe to an IMAP folder and were able to reproduce the issue with that module to.

It seems the pressure from many finally resulted in Microsoft prioritize this issue and roll out a fix, finally :-)