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Exporting PSTs and Setting Up External Forwarding | Lazy Admin Blog

As a “Lazy Admin,” I like to keep my cheat sheets handy so I don’t have to look up the same syntax every time a request comes in. Today’s snippets cover exporting mailboxes to PST and the “correct” way to forward mail to an external address.
1. Exporting Mailboxes to PST
Whether you are decommissioning a user or just taking a backup, New-MailboxExportRequest is your best friend.
Note: Ensure your Exchange Trusted Subsystem has read/write permissions on the network share before running these.
Export a Standard Mailbox:
New-MailboxExportRequest -Mailbox "Mailbox Name" -FilePath \\Sharelocation\Export.pst -DomainController DC_FQDN
Export a Mailbox Archive:
If the user has an In-Place Archive enabled, use the -IsArchive switch:
New-MailboxExportRequest -Mailbox "Mailbox Name" -IsArchive -FilePath \\Sharelocation\Archive.pst -DomainController DC_FQDN
2. Reconnecting a Disconnected Mailbox
If you have a disconnected mailbox that needs to be linked to a user account:
Connect-Mailbox -Identity "Mailbox Name" -Database DBName -User "UserName"
3. Forwarding Mail Externally (The Right Way)
To forward mail to an external address (like a Gmail or Outlook account), you shouldn’t just type an address into a transport rule. The cleanest way is to create a Mail Contact.
Step A: Create the Contact
- Login to Exchange Admin Center > Recipients > Contacts.
- Click Add > Mail Contact.
- Give it a sensible name.

Pro Tip: If you don’t want this contact cluttering up your Global Address List (GAL), hide it with PowerShell:
Set-MailContact "ALIAS-NAME" -HiddenFromAddressListsEnabled $true

Step B: Enable Forwarding via GUI

- Go to Recipients > Mailboxes.
- Locate the user you want to forward from and click Edit.
- Go to Mailbox Features > Scroll down to Mail Flow > View Details.
- Check Enable Forwarding.
- Browse and select the Contact you created in Step A.
- Optional: Check “Deliver message to both forwarding address and mailbox” if you want a copy kept in the original inbox.

Step C: Enable Forwarding via PowerShell (The Lazy Way)
If you don’t want to click through the GUI, just run this:
Set-Mailbox -Identity "Internal User" -ForwardingAddress "ExternalContactAlias" -DeliverToMailboxAndForward $true