# Migrating to MsgFiler 4

Support has ended for MsgFiler Classic. If you have upgraded to macOS Sonoma and are lamenting the fact that Mail Plug-Ins have been removed from the Mail app, you should purchase MsgFiler 4.

There are many new features in MsgFiler 4 that users have requested over the years, including:

* favorite mailboxes
* recent mailboxes
* ability to create new mailboxes from within MsgFiler
* configurable default action
* exclude mailboxes
* match on mailbox names only
* restrict search to selected accounts
* full keyboard access

## Differences Between the Application and Classic Plug-In

The previous version of MsgFiler came in the form of an [Apple Mail Plug-in](https://msgfiler.com/support/mail-plugins-explained/). Because the Mac App Store guidelines restricts plug-ins, MsgFiler has been rewritten to be a standalone application that communicates with Mail via [AppleScript](http://en.wikipedia.org/wiki/AppleScript). Differences between the plug-in and the application are noted below:

* **Hide Offline and Inactive Accounts**\
  MsgFiler 3.0 does not have the ability to determine whether a mail account is offline or inactive.
* **Mark as Read**\
  Due to AppleScript performance issues, the Mark as read feature has been removed from the application. From within MsgFiler, however, you can press `Command-Shift-U` to toggle the read/unread status of messages before you file them.
* **Loading Mailboxes**\
  The plug-in, by virtue of being integrated with Mail, is faster at loading and reloading of mailboxes.
* **Filing To Remote Mailboxes**\
  MsgFiler’s performance is slower than filing with the plug-in because MsgFiler must use AppleScript, whereas MsgFiler Classic has access to an internal method within the Mail application for filing.