"No Service" or "SIP Registration Failed"

Overview

If your campus phone displays "No Service" or "SIP Registration Failed", the phone has likely lost its connection to the university phone system. In most cases, this occurs when a phone has been disconnected from the network for an extended period of time and its saved configuration is no longer current. Resetting the phone's configuration typically resolves the issue and can often be fixed without requiring an on-site visit.

Symptoms

You may be experiencing this issue if:

• The phone screen displays "No Service" or "SIP Registration Failed"
• The phone's status light appears orange
• You are unable to make or receive calls
• The phone only provides an option to view additional details on the screen

These symptoms indicate that the phone is no longer successfully registered with the phone server.

Resolution Steps

Follow the steps below to clear the outdated configuration and reconnect the phone to the phone system:

Step 1: Open Details

When the error appears, select Details on the phone screen.

Step 2: Open Diagnostics

From the Details menu, select Diagnostics.

Step 3: Clear Configuration

Within the Diagnostics menu:

1. Select Clear Configuration
2. Confirm the action using the small black buttons located beneath the display screen.

Step 4: Allow the Phone to Restart

The phone will automatically reboot and download the latest configuration from the phone server. After startup completes, service should be restored.

Why This Happens

Campus phones use SIP (Session Initiation Protocol) to communicate with the phone system. If a phone remains disconnected from the network long enough, its stored configuration can become outdated, preventing successful registration with the phone server. Clearing the configuration forces the phone to retrieve fresh settings and establish a new connection.

If The Issue Persists

If the phone still displays "No Service" or "SIP Registration Failed" after completing the steps above:

1. Verify that the network cable is securely connected.
2. Try unplugging and reconnecting the network cable.
3. Contact the IT Help Desk for further assistance.
4. A technician may need to investigate the network connection, wall port, or phone configuration. Previous troubleshooting has shown that network connectivity issues can occasionally require additional investigation.