Close Sage 50 Accounting,
or make sure it is running in multi-user
mode.
When you installed
Sage 50 Accounting, a new Synchronization toolbar was added to Outlook.
If this toolbar is not visible when you open Outlook, in the toolbar area,
right-click the mouse and choose Sage 50. You may also need to restart Outlook if the Sage 50 toolbar option isn't available.