Title: Some users may be unable to access their user or archive mailbox using the Outlook desktop client or Outlook on the web
User impact: Users may be unable to access their user or archive mailbox using the Outlook desktop client or Outlook on the web.
More info: While we focus on remediation, we’ve temporarily suspended mailbox migrations to prevent additional impact. As such, some admins may be unable to migrate Exchange Online user mailboxes until impact is resolved.
Current status: We’ve confirmed that the offending service update, which was originally meant to address an unrelated code issue, introduced a conflict that’s resulting in this issue. We’ve observed that the reversion of this update is progressing, and we anticipate that it will be nearing completion by the time of our next scheduled update.
Scope of impact: Impact is specific to some users, who are served through the affected infrastructure, attempting to access their user or archive mailbox using the Outlook desktop client or Outlook on the web.
Start time: Tuesday, October 10, 2023, at 10:00 PM UTC
Root cause: A recent service update, meant to address an unrelated code issue, introduced a conflict that is resulting in impact.
Next update by: Friday, October 20, 2023, at 5:30 PM UTC
