Some users may be unable to access their user or archive mailbox using the Outlook desktop client or Outlook on the web

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 focused on remediation, we temporarily suspended mailbox migrations to prevent additional impact. We’ve now re-enabled mailbox migrations since the revert is successfully being applied for remediation. As such, admins can now resume migrating Exchange Online user mailboxes.
Current status: The fix currently stands at 96 percent saturation and anticipate its completion by the 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: Wednesday, October 25, 2023, at 6:30 PM UTC