The Office 365 team just announced that the length of time items remain in the Deleted Items folder in Exchange Online has been extended to indefinitely or according to the duration set by your administrator.
Previously deleted items would disappear after being in that folder for 30 days.
Read more about this change here:
- OFFICE BLOG: Extended email retention for deleted items in Office 365
http://blogs.office.com/2015/02/20/extended-email-retention-deleted-items-office-365/
kurtsh
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