Outlook’s email scheduling feature is there to answer your needs for convenience. However, there is a limitation to it on Windows. According to Microsoft Support, your scheduled email will only be sent if the Outlook app is open and connected to the internet during the specified time. If it isn’t, your email will stay in the Outbox folder until you open Outlook again. Only then will the message be sent to your recipient.
On the other hand, the Outlook app on Mac devices can still send your scheduled email even if the app isn’t open during the date and time you initially set. The same is true for scheduled emails made on the Outlook web app (outlook.com). The message will automatically be sent even if you’re not online. That said, if you’re looking to schedule an email without having to worry about having to open Outlook, it’s better to use the Mac or web app.
