A Large Number of Emails Were Falsely Flagged as Spam by ‘SpamCop’ on Sunday

Written by Bill Toulas
Last updated July 14, 2021

Cisco’s SpamCop, a state of the art email spam reporting service, has suffered an unusual kind of outage yesterday, resulting in a large number of “perfectly good” emails being flagged as spam. As the sun rose Monday, mail admins and service providers realized they were dealing with a situation, as large volumes of outgoing emails were inexplicably blocked and listed in SpamCop’s “blacklist.” After some digging into the matter, Cisco realized the ‘’ domain had expired, and all mail was rejected.

Thankfully for Cisco, nobody took the chance to snatch the domain, so the tech solutions expert was able to restore the service within a couple of hours (at 1:00 PM EST). However, depending on the DNS you’re using, you may continue to experience some lookup errors for a little while longer, although things should return to normal function for everyone globally within the day.

Once the domain expired, the IP address resolved to a domain parking service, so the service’s blacklist prevented everything from reaching its intended destination. So, basically, it’s an infinite situation of false positives. Interestingly, some users on social media had noticed the expiration date of the particular domain and even warned about opportunistic registrations, yet Cisco somehow missed this.

Someone who claims to be the founder of SpamCop but no longer associated with it stated that Cisco is totally ignoring his messages, and by extension, the platform, even though a respectable number of entities use it. A few users claim to have contacted Cisco’s emergency hotline but got hung up multiple times without receiving any assurances or explanations. So, all in all, it appears that the company has failed on multiple levels, something pretty unwonted for the American tech giant.

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