Final Status: The investigation determined that there was a temporary issue affecting routing of requests to Yammer.com. This issue has been resolved and engineers have confirmed that the service is no longer impacted. The root cause is under investigation.
User Impact: Affected users were unable to sign in to Yammer.com.
Customer Impact: Analysis of incident scope indicated that many customers appeared to be impacted by this event. For those customers affected, this issue potentially affected any user attempting to log in to the service. Some customers reported that their organization was affected by this issue.
Incident Start Time: Wednesday, January 6, 2016, at 7:21 PM UTC
Incident End Time: Wednesday, January 6, 2016, at 7:50 PM UTC
Preliminary Root Cause: The root cause of this incident is not known but is under investigation. Based on the impact of this incident the root cause will be provided, if identified, within 30 days.
Next Steps: The following is a list of known action item(s) associated with this incident. As part of the Office 365 problem management process, additional engineering actions may be identified to improve the overall service.
– Action: Review the monitoring infrastructure for improvements as this event was reported by customers before the investigation prompted a communication to be published to the Service Health Dashboard.
– Action: Identify the underlying root cause and develop a solution to prevent reoccurrences.
Please consider this service notification the final update on the event.