If you have upgraded to macOS Monterey 12.1, your MsgFiler mail plugins may have been disabled. If so, please upgrade to the latest versions of the plugins:
- MsgFiler Engine: Version 1.6.1 works with macOS 12.1. This is the plugin you should install if you are purchased MsgFiler from the Mac App Store.
- MsgFiler Classic: Version 2.6.1 works with macOS 12.1.
If you are running a previous version of macOS, such as Big Sur, Catalina or Mojave, you should not need to do anything.