Outlook

Microsoft is working on fixing an issue affecting some Outlook for Microsoft 365 customers and preventing them from accessing emails and their calendars.

"After updating to Outlook Version 2303 (Build 16227.20212) Users may be unable to view or access Microsoft 365 group calendars and email messages in Outlook Desktop," the company said in a support document published on Thursday.

"Affected users are part of a Microsoft 365 group. Some affected users may also notice that impact self-resolves after some time, although impact may also reoccur at a later time."

Outlook users affected by this issue may have problems when trying to perform one of the following actions while using the Outlook desktop client:

  • Add or access the group mailbox
  • Add or access the group calendar
  • Add, remove, or edit group members
  • Change mail items, such as marking as read, archive, or moving email to other folders

The buggy Outlook version was released to the Current Channel more than two weeks ago, on March 28.

Among a long list of feature updates and bug fixes, it also addressed a known sign-in issue preventing customers from accessing their account since at least October 2022, with "You cannot log in with a personal account. Use your work or school account." errors.

Workaround available

Microsoft says the Outlook Team is working on a solution to address this known issue and shared a temporary workaround until a fix rolls out for those experiencing problems while trying to access emails.

Affected customers are advised to use Outlook Web Access (OWA) if they want to use the Groups feature or revert to Outlook Desktop build 16130.20332, which isn't impacted by this issue.

The detailed procedure required to ever to the previous, unaffected Outlook build requires you to:

  1. Open a Command Prompt (Run as Administrator).

  2. Type/paste the following commands and press Enter after each:

    cd %programfiles%\Common Files\Microsoft Shared\ClickToRun   

    officec2rclient.exe /update user updatetoversion=16.0.16130.20332

  3. In the backstage, disable Updates (File, Office Account, Update Options, Disable Updates).

  4. Set a reminder on your calendar for May 9, 2023, to remember to re-enable updates. The fix should be out sooner, but May 9 is Patch Tuesday, and the fix will be in this update.

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