Exchange Mailbox Issue Triage Playbook

Use this when users report shared mailbox sync problems, missing messages, archive issues, or delegate access trouble.

First split the problem

Commands

Connect-ExchangeOnline
Get-Mailbox shared@company.com | FL ArchiveStatus,ArchiveState,RetentionPolicy
Get-MailboxPermission shared@company.com | ? {$_.User -notlike 'NT AUTHORITY*'}
Get-RecipientPermission shared@company.com
Get-InboxRule -Mailbox shared@company.com
Start-ManagedFolderAssistant -Identity shared@company.com

Escalation notes

Include mailbox address, impacted users, OWA test result, Outlook version, cache mode setting, permission output, and whether the issue affects all delegates or one user.