A malfunction of the Microsoft Exchange mail server caused a lot of frustration. The problems are now fixed.

Yesterday was another award for Microsoft. A Microsoft Exchange malfunction meant that business customers were no longer able to access their mailbox and/or were unable to send or receive emails. The problem could be due to an error in the file Directory-based edge blockingFunction that allows administrators to manage mail traffic in Exchange.

Around 9pm last night, Microsoft tweeted that the outage was resolved by redirecting Exchange Online Protection traffic. Today, all mail traffic should be able to go in and out normally again. However, it is not yet clear whether emails that were blocked yesterday will still end up in your mailbox.

Malfunctions at Microsoft

Technical issues with Microsoft services seem to be a tradition these days. At the end of January there was a first major outage that paralyzed several Microsoft 365 applications. It turned out to be due to a misconfigured IP address on a WAN router.

Since then, Outlook in particular has caused frustration. Two weeks after the first outage, the mail service took another day off and a week ago mailboxes were overloaded with spam mails and there was a synchronization problem with Gmail. Any online service can go wrong, but when it happens at Microsoft, it has an immediate impact on the daily operations of thousands of businesses.