From: O365 Mail <c83b72dd001482ce10f0b106c7a0ed0e[AT]hockeyapp[DOT]net>
Subject: Invalid security certificate
To: E…o

At 8:02 AM, your mailbox es…u failed to sync and returned (3) incoming mails.

Syncing failed to go through due to invalidation of your mailbox within the past 15 days.

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