--- title: "Receiving a Busy Signal/Call Drop when a Ring Group Forwards out to an External Line" slug: "receiving-busy-signal-call-drop-when-ring-group-forwards-external-line" updated: 2026-06-30T07:22:37Z published: 2026-06-30T07:22:37Z canonical: "help.8x8.com/receiving-busy-signal-call-drop-when-ring-group-forwards-external-line" --- > ## Documentation Index > Fetch the complete documentation index at: https://help.8x8.com/llms.txt > Use this file to discover all available pages before exploring further. # Receiving a Busy Signal/Call Drop when a Ring Group Forwards out to an External Line ### Symptom: When using a Ring Group to dial out to an external line, you receive a busy signal/call drop. ### Applies to - Admin Console - Ring Groups ### Resolution For a Ring Group to forward calls out to an external number, the phone number receiving the inbound call must be assigned to a user or service first. **An unassigned number will not support forwarding to an off‑net (external) destination.** You need to involve a user/number in some way: - One method would be to assign a number to the Ring Group. - Another method is to forward calls from the Ring Group to a user or Auto Attendant and then configure that user/Auto Attendant’s call forwarding rules to dial out to the external number. The above approaches rely on a number being associated with either the Ring Group, with a user or extension that handles the external forwarding. > [!NOTE] > Note: > > Essentially, when placing a call to the Ring Group to eventually dial out to the external line from the Ring Group that is not assigned to a number, there is no phone number to associate with the call, and the carrier rejects it with a **403 FORBIDDEN.** ### Causes - Concurrent external calls has been reached - No user/service/number is assigned to the Ring Group