We are a small / medium business running Exchange 2010 with Outlook 2010 Professional clients. We utilize Exchange in place archiving. The Exchange server was updated to UR 32 on 3/10/21 I'm not sure when previous UR's were installed because I can't find a way to see the dates of installations, but I'd estimate that it had been at least a year since any UR's were installed on the Server prior to 3/10/21.
Regardless, on 2/26/21 I received my first complaint of this issue from a user. The user stated that they were unable to see their archive folder in Outlook. I logged in and deleted their Outlook profile and created a new on and they were fixed.
Over the course of troubleshooting this, I've discovered that not only do the archives disappear, but the scheduling / free busy data is unavailable, and they are unable to set their out of office through Outlook (it reports the server as unavailable). Recreating the profile fixes all three of these.
This has happened on a handful of clients over the last several months, it has never happened to me. Maybe 1 or 2 times every other week I'd get this reported and I'd fix it and it would go away - no big deal.
On certain users however, it keeps happening over and over again. Recreating the profile will fix the problem for an indeterminate amount of time, sometimes many months, sometimes a couple of weeks, but then it happens again. I have probably in the neighborhood of 5-10 users where it has happened 3 - 4 times each, though others have never reported the issue again. But It's hard to gauge because many users do not use archives, free/busy, or out of office. The original user on 2/26/21 however has never had the issue again.
After not being able to find any info on this, and posting a less detailed version of this problem already some months ago, I'm posting again to see if I can list everything I've learned and maybe find a permanent solution.
About the only advice I got from my previous post on this forum was to disable cached exchange mode, which I did, but it did not resolve the issue.
There are times where I don't get any reports of this for several weeks, then I get 2 or 3 at a time.
I have tried using the "Repair" option under Account Settings, which always initially fails to find the account information, then cancelling it, quitting Outlook, and running it again causes it to immediately say that the problem is corrected and to restart Outlook. Upon restarting Outlook, the archive folder is there, but in about 20-30 seconds it will disappear off the screen in front of my eyes. Sometimes redoing the repair several times will get it to stick, and other times I have to recreate the profile.
I took three registry dumps of the Outlook profile during the above process, one when it was "broken", one when it was "repaired", and one after I restarted and it was "working". Aside from some minor differences, the big difference is that the broken one is missing the entire key which references the guid to the archive mailbox. When you repair the mailbox it comes back, and when it breaks again, it deletes that key. Unfortunately all the keys are random names, so I can't just tell you what key it is. The key in question contains 17 REG_BINARY keys and two REG_SZ, 001e660c which gives the name of the Exchange server, and 001e660b which gives the name of the archive mailbox
"001e660b"="/o=xxxxxxxx/ou=Exchange Administrative Group/cn=Recipients/cn=xxxxxxxxxxxxx/guid=f1b7334f-053d-4c63-ae36-09611f2da4db"
All of these features work 100% ok on the OWA side of things, and it seems to be completely limited to the Outlook profile in registry.
All clients are Windows 10.
So, something for some reason is deleting the key referencing the archive guid in the Outlook profile. I don't know if it's also changing other keys regarding the free/busy / Out of office, but I figure if anybody can help explain why this key is being deleted, that would be a huge start.
I know 2010 is eol but it works great otherwise and there's no justification feature wise to update to anything newer and O365 is simply too expensive. I would consider upgrading the Exchange server itself if I could point to it as being the issue, but there's no indication that there's any issue on the Exchange side of things.
Any help would be very appreciated. I don't mind fixing the issue, but I feel bad for the users who are hitting this issue repeatedly.