This is has now been confirmed resolved, and more than half of the affected mails have been subsequently released.
Posted 8 months ago. Mar 28, 2018 - 12:41 BST
We believe this is issue has now been resolved. we will have another update within the hour to confirm 100%
Posted 8 months ago. Mar 28, 2018 - 11:23 BST
Started: 3/28/2018 10:48 GMT
Components: Email Inbound, Email Outbound
Locations: Europe and Australia
Due to a single false virus filter definition it may come to bounce messages inbound / outbound. All False Positives will be released during the next hour.
Posted 8 months ago. Mar 28, 2018 - 10:55 BST
We are currently experiencing a temporary issue with outbound email being incorrectly tagged and quarantined as being a virus, with the reason "virus-scan02". Our 3rd line engineers are currently working on a resolution as a matter of extreme urgency.