If users need to access their voicemail messages when they are away from the office, you can set up an Incoming Call Route in IP Office Manager with the destination as Voicemail. See the IP Office Manager help or guide.
Procedure
Open IP Office Manager
In the Navigation pane, click Incoming Call Route and add a new call route.
In the destination field, select the option Voicemail.
When an incoming call is matched the call is passed to voicemail to enable remote mailbox access. Callers are asked to enter the extension ID of the mailbox required and then the mailbox access code.
Click OK to save the changes.
Click to merge the configuration back to the IP Office.