Repeat for the steps for each email account you want alerts on. Click Next again and complete the rule.Choose Display a Desktop Alert (and Play a sound, if desired) as the Action(s).Click Next twice to apply the rule to all messages sent to this account.Choose Apply rule after messages arrive.
Next, create a rule for the accounts you want to receive a notification for. If you have Play a sound or Show an envelope in the taskbar enabled, you can turn those off too. In Outlook for Windows, turn off global notification in File, Options, Mail by unticking Display a Desktop Alert.