Widespread outage for Yahoo email

Yahoo Sign

Yahoo Mail users took to Twitter Tuesday with the hashtag #yahoomaildown to complain about an email service outage.

While the main Yahoo website was not affected, many users could not access the email portal.

Yahoo told CNBC that it is aware of the login issues for some users on its network.

"Our engineering team is working hard to resolve the issue," spokeswoman Anne Yeh said. "We apologize for the inconvenience."

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-With reporting by CNBC's Josh Lipton and Ryan Ruggiero