Custom notification sounds on multiple accounts in New Outlook

No. In the screenshot, All accounts only means that every listed account is allowed to send Windows notifications. It does not copy the primary account’s selected sound to the other accounts.

Try this:

1. Open New Outlook Settings > General > Notifications.
2. If an account selector appears, select each account separately and enable mail notifications and sound.
3. Keep Allow notification sounds enabled in Windows and leave the account setting on All accounts.
4. Send a test message to each mailbox.

If secondary accounts still use the default sound, this is a New Outlook multi-account limitation or bug. Windows treats them as notifications from the same Outlook app and provides no setting to force one custom sound across all accounts.

The practical options are to use the default sound for every account, report the behavior through Help > Feedback, or use Classic Outlook rules if different sounds are essential.

Hi, 

Based on the setting shown in your screenshot, I can understand why you would expect the same notification sound to apply to all accounts when 'All accounts' is selected.

However, Microsoft doesn't describe how custom notification sounds are handled in a multi-account scenario in the new Outlook.

If notifications are being generated for all accounts but only the primary account uses the custom sound while the others continue to use the default sound, I haven't found any documentation indicating whether this is expected behavior or a known limitation.

A few things I would test:

• Check whether the issue occurs with different account types (Exchange Online, Outlook.com, Gmail, IMAP).
• Remove and re-add one of the secondary accounts.
• Test on another device using the same profile.
• Reset the new Outlook local cache and let Outlook rebuild its local settings.
• Check whether the behavior changes when a secondary account is set as the primary account.