Phone Not Ringing? DND, Forwarding, and Routing — In That Order

When a phone doesn't ring, the cause is almost always a setting silencing it on purpose: Do Not Disturb, a zeroed ringer, or call forwarding. Check those three at the phone before involving an administrator — they account for the large majority of "my phone is broken" reports.

Check at the phone (30 seconds)

1. DND — is a Do Not Disturb icon on the screen? Press the DND key to clear it. This is the number-one cause.
2. Ringer volume — press volume-up while the phone is idle.
3. Forwarding — a forward icon means calls are being sent elsewhere; disable forwarding from the phone's menu or ask your admin.

If callers say it rings once then voicemail

The extension's ring duration may be set very short, or a second device on the same extension is in DND and answering logic is misbehaving. An administrator can check both in a minute.

For administrators

• Confirm the device is registered (Last Seen current).
• Check the extension for forwarding rules and ring duration.
• Confirm the caller dialed the number you think they did — then follow that number's destination. A number pointed at an old route or menu quietly explains many "random missed calls."
• Test internally (ext-to-ext) vs. externally: internal rings + external doesn't = routing; neither rings = device/extension.

Related articles

• Phone won't register
• Pointing a phone number at a destination