In Notes 6.x and 7.x, a custom mail sound can be set via Mail preferences within User Preferences.
1. File --> Preferences --> User Preferences
2. Mail tab --> General sub tab
3. Under heading "When New Mail Arrives", click the check box to play a sound. Click the browse button and find a cool sound.
Notes:
You can also optionally select to show a popup message, system tray icon, and automatically refresh the inbox.
Desktop policies set by Notes administrators can restrict access for users to adjust their user preferences. If you cannot change one of these options, contact your Lotus administrator and/or Help Desk.
 Obsolyte Steps for Notes 4: |