Refresh or check for new messages in Outlook

In classic Outlook, press F9, or go to Send / Receive and then select Send/Receive All Folders.

To check for new messages for one account, go to Send / Receive and select Send/Receive Groups. Then, for that account name, select Inbox.

In classic Outlook, you have the option to work offline—disconnected from the email server. When you do so, no messages are sent or received until you use the Send/Receive feature to temporarily reconnect to the email server. 

But here in the new Outlook for Windows, working offline is not supported. That means you're always connected to your mail server:

• Your new Outlook app automatically receives messages as they are sent to you, and

• Messages sent by you are likewise automatically delivered to the mail server as soon as you click Send.

As a result of this situation, there is no need for the new Outlook​​​​​​​ to have the same Send/Receive feature that is in classic Outlook. 

If you are interested in delaying the sending of specific messages, you can do that. See Delay email message delivery for more information.