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https://www.bleepingcomputer.com/news/security/microsoft-exchange-server-2013-reaches-end-of-support-in-90-days/
Microsoft warned customers today that Exchange Server 2013 will reach its extended end-of-support (EOS) date 90 days from now, on April 11, 2023.
Exchange Server 2013 was released in January 2013 and has already reached the mainstream end date more than four years ago, in April 2018.