If you would like to permanently disable the DMI drawer in Apple Mail, then do the following:
1. Quit Apple Mail.
2. Quit Daylite (if open).
3. Open a Finder window and check the following locations:
- Hardrive -> Library -> Receipts. If there is a file titled "DMI.pkg", please move it to the trash.
- Home -> Library -> Mail -> Bundles. If there is a file titled "DayLiteMailIntegration.mailbundle," please move it to the trash.
- Launch Apple Mail and you should find that the drawer no longer appears.