Image: Micosoft/ZDNet

The feature works by blocking email threads with over 5,000 recipients that have got more than ten reply all responses within an hour. It’ll keep them on hold and prioritise regular email traffic on the server first in order to keep communications open and to stop the customers’ servers from becoming overloaded.

“Once the feature gets triggered, Exchange Online will block all replies in the email thread for the next four hours, helping servers prioritize actual emails and shut down the Reply-All storm,” said ZDNet.

The report cited Microsoft’s own reply all woes, which once saw an email storm with 52,000 people in a reply all mess that clogged the Redmond-based company’s internal comms for hours. If it can happen to Microsoft itself, it can happen to anyone.