Why doesn't AutoArchive work? I ran it and nothing was archived; all of the folders in the archive.pst are empty.

Archiving has always caused a lot of confusion among users because Outlook archives items based on the last modified date, which may or may not be the received date (or start or completed date). This works well, for the most part, until you import messages or edit older messages, both of which changes the last modified date. If you wanted to archive by the received date (or start, or completed date) you either needed to move the mail yourself (move, not copy, or the modified date changes!) or use a 3rd party archiving tool.

Use AutoArchive to Automatically Cleanup the Deleted Item and Junk Email Folders

The default setting for AutoArchive is to use either the received/competed/start date or the modified date, whichever is later. The modified date is the received date or the completed date, unless you do something that affects the modified date after receiving a message or marking a task complete. Import & Export, copying, and editing items are among the things that will change the modified date.

Enable Archiving by Received Date

With the release of the Outlook 2010 April 26 2011 hotfix, users can now archive by the received date. This also supported in Outlook 2007, with a hotfix released in December 2010. It is not supported in earlier versions of Outlook.

These hotfixes support the ArchiveIgnoreLastModifiedTime registry setting, which lets you use the received, start, or completed dates as the archive date.

After installing the hotfix, you need to add the following value to the registry

Outlook 2016, Outlook 2019, Outlook 365 (subscription):

HKEY_CURRENT_USER\Software\Microsoft\Office\16.0\Outlook\Preferences
DWORD Value: ArchiveIgnoreLastModifiedTime
Value data: 1

Outlook 2013:

HKEY_CURRENT_USER\Software\Microsoft\Office\15.0\Outlook\Preferences
DWORD Value: ArchiveIgnoreLastModifiedTime
Value data: 1

Outlook 2010:

HKEY_CURRENT_USER\Software\Microsoft\Office\14.0\Outlook\Preferences
DWORD Value: ArchiveIgnoreLastModifiedTime
Value data: 1

In Outlook 2007, you'll add the value to this key

HKEY_CURRENT_USER\Software\Microsoft\Office\12.0\Outlook\Preferences
DWORD Value: ArchiveIgnoreLastModifiedTime
Value data: 1

With this value set to 1, you'll be able to archive based on the received, completed, or end date of an Outlook item:

• Email message: uses the received date.
• Calendar item: uses the actual date that an appointment, event, or meeting is scheduled for.
• Task: uses the completed date. Note that Tasks that are not marked as completed are not archived, and Tasks that are assigned to other users are archived only if the status is completed.
• Note: uses the last modified date and time.
• Journal entry: uses the date the journal entry was created.

Note that Contacts are never archived in any version of Outlook.
 

Do It For Me

If you don't want to edit the registry yourself, we have reg files you can download and run. Be sure to choose the correct one for your version of Outlook.
Outlook 2016, 2019, 365 Outlook 2013 Outlook 2010 Outlook 2007

If you use an older version of Outlook, you can use a utility to archive the messages.