Microsoft 365 Alert – Service Degradation – Exchange Online – Users can’t preview Microsoft Office app attachments in Outlook on the web – RESOLVED

Announcements Sourav Nandi

08/12/2023 09:10:00 AM

NHSMail Reference: INC40144131

Microsoft Reference: EX696674

Issue Status: RESOLVED

Issue Description: Users can’t preview Microsoft Office app attachments in Outlook on the web.

More Info: Affected users are unable to preview attachments from Office apps such as Word, Excel, and PowerPoint in Outlook on the web. While we work to remediate impact, users may be able to use the Outlook desktop and mobile clients as alternative methods.

Final Update: 13/12/2023 08:55:00 AM – Deployment of the fix is complete, and Microsoft have monitored their service telemetry to confirm that Microsoft Office app attachment previews are restored and impact is remediated.

Scope of impact: Users serviced by the affected infrastructure attempting to preview attachments from Office apps such as Word, Excel, and PowerPoint in Outlook on the web are impacted.

Root Cause: A recent service update, intended to improve the performance of the Web Application Client (WAC) infrastructure, has caused the inability to preview Microsoft Office app attachments in Outlook on the web.

Next steps: Microsoft are reviewing their Microsoft 365 for the web infrastructure update procedures pertaining to attachment preview functionality to prevent similar impact in future updates.