Outlook

According to reports from an increasing number of Microsoft customers, Outlook inboxes have been flooded with spam emails over the last nine hours because email spam filters are currently broken.

This ongoing issue was confirmed by countless Outlook users who have reported (on social media platforms and the Microsoft Community's website) that all messages were landing in their inboxes, even those that would have been previously tagged as spam and sent to the junk folder.

"I've received 36 spam emails in my inbox the past 2 hours straight. It's been happening for way too long and it just continues to get worse on an hourly basis," one user said.

"Seems to have begun happening between 10pm and midnight Eastern time (I have a successful junk mail at 10:04pm, and the first inbox junk mail at 12:17am)," another added.

Some say that even checking the "Only trust email from addresses in my Safe Senders and domains list and Safe mailing lists" in Junk Mail > Filters doesn't fix this issue, pointing to the webmail service's filtering being completely broken.

Despite the stream of customer complaints, the Office service status page shows that "everything is up and running."

Microsoft is yet to share a public statement confirming Outlook users' reports that spam filters are broken.

While today the spam filtering issue in Outlook seems to be particularly bad and affecting a massive number of customers, this has been going on for months, with some reporting seeing many spam emails landing in their inbox since at least November 2021.

Microsoft didn't reply to a request for comment when BleepingComputer reached out earlier today.


Update February 21, 00:32 EST: Microsoft has confirmed that spam and phishing emails are landing in the users' mailboxes. The company also says that some affected customers might experience "performance issues such as navigation delays and messaging latency in Outlook.com or Internet Message Access Protocol (IMAP) connections."

Update February 21, 08:06 EST: Microsoft says the spam filter issue has now been addressed.

"We've identified the source of the problem and taken action to fix it. Our service telemetry shows that the problem has been addressed, and we'll continue to monitor this telemetry to ensure the issue remains mitigated," Redmond said.

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