We have been made aware of certain users may be unable to send Exchange Online email messages. Affected users may receive the following error “503 5.5.1 bad sequence of commands”
The issue is currently with Microsoft who are reviewing service monitoring telemetry to isolate the root cause and develop a remediation plan.
We expect an update on the matter from Microsoft at 10:30 AM
Please be aware that the remediation work has now concluded and services have now been fully restored. All client platforms are once again fully operational. We will continue to monitor the platform following this.
Please be advised, remedial work is continuing to progress on the replacement hardware by Accesspoint engineers.
Engineers have replaced hardware at the datacentre and remedial work is now underway to configure the new hardware.
The issues at the data centre are still ongoing and investigation into the root cause is continuing. The issue has been isolated to a subset of servers and we will provide further updates as they become available.
Please be aware that Mimecast have now resolved the issue with UK email service and mail flow has now returned to normal.