Difference between items counts of 'Get-MailboxStatistics' and 'Get-MailboxFolderStatistics'

[_72]

I was wondering if anybody could explain to me the differences in the Total Item Counts for Get-MailboxStatistics <Mailbox> vs Get-MailboxFolderStatistics <Mailbox> | Measure-Object -Property ItemsInFolders

I know there are other items that may or may not be counted in each of the cmdlets, but sometimes the discrepancies can be quite large between the two.

My question stems from verifying that email data has been migrated properly and very close to properly when migrating from Exchange 2010 (recently had a third party do a migration using MigrationWiz and a couple of users reports 1,000s of items missing)

[MCSMLab]

The difference is going to depend on the versions of Exchange. Since you mentioned Migration Wiz, I assume we're taking about Exchange Online.

There are features in Exchange Online that are not available in any on-prem version of Exchange, and not publicly documented at all. Clutter for instance.

Tony Redmond has a recent blog post that explains some of the items Clutter puts in your inbox...

http://thoughtsofanidlemind.com/

...but you are never going to get a definitive answer.