well the thing is when you move users from say the 2 year group to the unlimited group, it isn't retroactive, it will only give the new retention to items going forward unless you have the update retention categories set properly in the archiving policy, which by default is turned off
Also it sounds like expiry was maybe done based on Modified Date instead of archived date?
Modified date means that it will expire items based on the Sent date of the email, where as archived date is when EV archived the item
So for instance if i receieved an email on 01/01/2005 and archived it 01/01/2009
Based on modified date and a 2 year retention, that email would be valid to delete on 01/01/2007, and if i ran expiry now, the item would be deleted
Based on archived date and a 2 year retention, that email would be valid to delete on 01/01/2011, and if i ran expiry now, the item would not be deleted
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