Exchange 2019 Recovery Monitoring Mailboxes

If those services are still stopped, start them again first. Microsoft Exchange Health Manager (MSExchangeHM) performs the monitoring-mailbox provisioning checks; leaving it stopped prevents that process from running.

Before trying to recreate anything, distinguish “not created” from “not visible”:

1. In Exchange Management Shell, query the whole forest:

   Set-ADServerSettings -ViewEntireForest $true
   Get-Mailbox -Monitoring -ResultSize Unlimited |
          Format-Table Name,ServerName,Database

   Also check Microsoft Exchange System Objects > Monitoring Mailboxes in Active Directory Users and Computers with Advanced Features enabled.
2. Confirm the services are running on both servers:

   Get-Service MSExchangeHM,MSExchangeHMRecovery

   Start any that remain stopped, then allow time for provisioning and AD replication before querying again.
3. Check database availability:

   Get-MailboxDatabaseCopyStatus * |
          Format-Table Name,Status,CopyQueueLength,ReplayQueueLength

   Resolve unavailable databases or relevant AD connectivity/replication errors before forcing mailbox recreation.
4. Review the Application event log and Exchange’s Logging\Monitoring folder around the Health Manager startup time. Look for mailbox provisioning errors, particularly access-denied or domain-controller lookup failures.

If provisioning reports access denied, investigate the permissions and inheritance on the Monitoring Mailboxes container rather than granting broad AD permissions. In a multi-site environment, also check which domain controller each server is using and whether it sees the same objects.

Don’t delete the Monitoring Mailboxes container or all existing health mailboxes yet. Since both servers are affected, the next useful evidence is the provisioning error from each server and confirmation of whether the AD objects exist. Stopping the two services alone won’t recreate them.