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troubleshooting a Cisco 7942 or 7962 phone for VPN use

This article will walk users through the process of troubleshooting a Cisco 7942 or 7962 VPN enabled phone.


Register the phone on a hosted voice connection

•    The phone first needs to be registered on a hosted provided voice connection if this has not or cannot be done the phone may need to be sent to a site that has this connection or replaced.
•    Once the phone has registered on the voice connection, you may plug the phone into any normal data internet connection.

Verify VPN is enabled

  1. On the phone press the “Settings” button
  2.  Select “Security Configuration” (option 4)
  3.  Select “VPN Configuration” (option 8)
  4.  Option 1 should be enabled
    4.1 If option 1 is disabled select the “Enable” soft key at the bottom of the screen.

Clear CTL and ITL files

  1. On the phone press the “Settings” button 
  2. Select “Security Configuration” (option 4)
  3. Select “Trust List” (option 5)
  4. CTL file (option 1) should read “Not Installed” & ITL File (option 2) should read “Not Installed”. 
  5. If either of these show anything other than “Not Installed”: 
  6. Press **# to unlock the settings
  7. Select the file using the “Select” soft key
  8. Press “Unlock” using the soft key
  9. Press the “More” soft key
  10. Select the “Erase” soft key

Verify TFTP settings on phone

  1. On the phone press the “Settings” button
  2. Select the option “Network Configuration” (option 2)
  3. Select “IPv4 Configuration” (option 1)
  4. Scroll to “Alternate TFTP” (option 16) and it should read “Yes”
  5. Scroll to the “TFTP Server 1” (option 17) and it should read “<client TFTP server IP>”
  6. If the “Alternate TFTP” is set to “No” or “TFTP Server 1” is incorrect:
  7. Press **# to unlock the settings
  8. Highlight “Alternate TFTP” (option 16)
  9. Press the soft key labeled “Yes”
  10. Scroll to “TFTP Server 1” (option 17)
  11. Press the soft key labeled “Edit”
  12.  In the new screen enter “<client TFTP server IP>”
  13. Press the “Validate” soft key
  14. Press the “Save” soft key
  15. The phone may reset itself after these changes

Other Troubleshooting Steps  

  • If VPN authentication fails, press the “Retry” soft key (you may need to press this button multiple times).
  • If phone still fails to connect after multiple times, unplug the phone so that it powers completely off, then plug it back in and try to connect again.

Contact Support

  • If the problem persists, or TFTP server information is needed after multiple attempts contact the support team for further assistance. 
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