With a Microsoft Exchange Server or Office 365 account, you can work offline to avoid connection charges or stop Outlook from attempting to send and receive messages over a slow network connection.
- Click Send / Receive > Work Offline.
When Outlook switches between working online and offline, all email accounts are changed.
You know you’re working offline when Work Offline is highlighted on the ribbon or Working Offline appears on the status bar at the bottom of the Outlook window.
When you’re ready to work online again, click Send / Receive > Work Offline. The button text doesn’t change, but it’s only highlighted when you’re working offline. Working Offline on the status bar also goes away when you’re working online.