How can I forward calls to an external number?

From VoiceMailTel

Login to your VoiceMailTel online portal account -> click on your extension (from the left menu) -> click on Call Routing -> choose the fourth step, Forward to external numbers -> enter the numbers you want your calls to be forwarded, by priority -> click the Save button at the bottom of the page

Note: Make sure you don't forget to enter the desired TimeOut (time for the call to ring before being directed to voicemail) for all your forwarding rules