Hi James,
Licensing is based on user-mailboxes being archived, not being functional (group) mailboxes.
What we do in AD is to change a Leavers Displayname to have "ZZ Disabled" in front of the original displayname. that way, they archivename also changes during the 'leavers archiving" process.
To verify the required number of licenses, I run a query:
USE EnterpriseVaultDirectory
SELECT DISTINCT NrUsers=COUNT(MbxNTUser)
FROM ExchangeMailboxEntry
WHERE (MbxArchivingState = 1)
and mbxdisplayname not like 'fm.%' -- Functional Mailbox
and MbxDisplayName not like 'rs.%' -- Resource Mailbox
and legacymbxdn not like '%/cn=fm.%' -- Functional Mailbox
and legacymbxdn not like '%/cn=rs.%' -- Resource Mailbox
and mbxdisplayname not like '%ZZ disabled%' -- Disabled users
and mbxdisplayname not like '%ZZ Old%' -- obsolete archives
Manual tidy up....
You can have the usage report, based on billing account. where it shows a SID, the account no longer exists. Or, in the VA Con the Archives, sort on Billing Account.
You can then use a sql to change the archivename, or do it manually.
To change the name, I use this:
Update Archive
Set ArchiveName = 'ZZ Disabled - ' + ArchiveName
Where (ArchiveName = 'name of archive with SID as billing account')