Missing Archive Statistics in ODM Despite Active Archive Mailboxes (4379576)

When collecting mailbox statistics in On Demand Migration, certain archive mailboxes are missing from the results. This happens even though users can access these mailboxes and the archive appears to be working as expected.

This issue occurs due to the way the ArchiveStatus property is reported in Microsoft 365. ODM relies on the ArchiveStatus object to detect and collect archive telemetry. Our investigation revealed that:

• Mailboxes with ArchiveStatus set to Active are collected correctly.

• Mailboxes with ArchiveStatus set to None are not collected during statistics gathering.

Despite showing "None," these archives are active and functioning. They have valid ArchiveGuid and ArchiveDatabase properties, and users can access their contents.

Microsoft notes that the ArchiveStatus may show as "None" under certain conditions, such as:

• The user was recently re-licensed for an archive mailbox.

• A mailbox was migrated from on-premises to Microsoft 365, including both primary and archive components.

At this time, no immediate fix is available, but the issue is being reviewed for possible enhancement in future ODM versions.

As a temporary measure:

• Be aware that archive mailboxes with ArchiveStatus: None may be excluded from statistics reports, even if active.

• You can verify archive status by checking other mailbox properties like ArchiveGuid and ArchiveDatabase, and confirming user access.

Our team has raised a work item to explore enhancements that would allow ODM to recognize and collect stats for archives with ArchiveStatus: None.

For reference, Microsoft’s documentation on this behavior can be found here:
ArchiveStatus is set to None for an active archive mailbox – Microsoft Learn