If your desk phone is not working, the issue may be related to power, network connection, phone settings, Webex Calling service, or a temporary communication problem.
MCC supports Webex Cloud Calling and Cisco desk phones. Before requesting service, use the steps below to help identify whether the issue affects only one phone, multiple phones, or the entire phone system.
Step 1: Check Whether the Phone Has Power
Start by looking at the phone display.
If the screen is blank, dim, or not responding, check:
- Is the phone plugged in?
- Is the network cable connected securely?
- Is the cable connected to the correct port?
- Is the phone connected to a working network jack?
- Was the phone recently moved?
- Is the phone using a power adapter (plugged into the wall) or Power over Ethernet (powered through the network cable)?
Many desk phones receive power through the network cable. If the cable is loose or plugged into the wrong port, the phone may lose both power and network connection.
Step 2: Check the Network Cable
Cisco desk phones usually connect through an Ethernet cable.
Make sure the cable is firmly connected to the phone and to the wall jack, network switch, or other approved connection point.
If the phone has a computer connected through it, check both cables:
- Wall/network cable to the phone
- Phone cable to the computer
If the computer connected through the phone also lost network access, the issue may be with the network jack, cable, or switch.
Step 3: Restart the Phone
A restart can clear temporary issues.
To restart the desk phone:
- Make sure the phone is not in use.
- Unplug the network cable or power cable from the phone.
- Wait at least 30 seconds.
- Plug the cable back in.
- Allow the phone to fully restart.
- Watch for any messages on the screen.
The phone may take several minutes to reconnect to Webex Calling.
Step 4: Check for Messages on the Screen
Look for any message displayed on the phone, such as:
- Network unavailable
- Registering
- Phone service unavailable
- Authentication error
- No service
- Line not registered
- Emergency calls only
- Firmware update
- Date or time error
Write down the exact message or take a photo before restarting or clearing anything. The screen message can help MCC determine whether the issue is with the phone, network, account, or Webex Calling registration.
Step 5: Test Incoming and Outgoing Calls
If the phone has power and appears connected, test both incoming and outgoing calls.
Try:
- Calling another internal extension
- Calling an outside number
- Having someone call your direct number
- Testing voicemail
- Checking whether calls ring in the Webex App
This helps identify whether the issue affects all calling, only outside calls, only inbound calls, or only that desk phone.
Step 6: Check Whether Other Phones Are Working
Ask nearby users whether their phones are working.
If only one phone is affected, the issue may be with that phone, cable, network jack, or user setup.
If multiple phones are affected, the issue may involve the network, internet connection, firewall, Webex Calling service, or a broader system issue.
If all phones are down, contact MCC right away.
Step 7: Check the Webex App
If your user is set up for the Webex App, check whether calls work there.
If calls work in the Webex App but not on the desk phone, the issue may be specific to the physical phone, cable, or phone registration.
If calls do not work in either the Webex App or the desk phone, the issue may be related to the user account, calling service, network, or call routing.
Step 8: Check for Recent Changes
Desk phone issues often happen after something changes.
Consider whether your office recently had:
- Internet outage
- Power outage
- Network switch replacement
- Firewall update
- Office move
- Desk relocation
- New phone installation
- User change
- Extension change
- Webex Calling update
- Cabling work
- Router or modem replacement
Include recent changes in your service request. “It stopped working after we moved desks” is extremely useful information. “It just hates us now” is less useful, though possibly accurate.
Step 9: Check Headset or Audio Issues
If the phone powers on and calls connect, but audio is not working, check the headset, handset, and speaker.
Try:
- Picking up the handset
- Using speakerphone
- Disconnecting and reconnecting the headset
- Checking mute
- Checking volume
- Trying another headset, if available
If callers can hear you on speakerphone but not through the headset, the issue may be with the headset rather than the phone.
When to Contact MCC
Contact MCC if:
- The phone screen is blank and will not power on
- The phone says it cannot register or connect
- The phone has no dial tone
- Calls fail inbound, outbound, or both
- Multiple phones are down
- The issue started after a network or office change
- The phone repeatedly disconnects
- Audio does not work after checking headset and volume
- The phone displays an error message
- You are not sure what to check next
For urgent phone outages, call MCC instead of relying only on email.
What to Include in Your Service Request
When requesting help, include:
- Business name
- Contact name
- Phone number
- User’s name
- User’s extension or direct number
- Desk phone model, if available
- Location of the phone
- Message shown on the phone screen
- Whether one phone or multiple phones are affected
- Whether the Webex App is working
- Whether inbound calls, outbound calls, or both are affected
- Any recent network, power, office, or user changes
- Photos of the phone screen, if helpful