Download the necessary firmware off Cisco's site.

In the router, change the tftp server option to a TFTP server. On my particular router, telnet to the router, then execute the following instructions, where 192.168.1.105 is the IP address of the TFTP server.

  1. system-view
  2. dhcp server  ip-pool vlan1 extended
  3. tftp-server ip-address 192.168.1.105

On the TFTP server, run tftpd32. Do not use tftpd64. (These are by Ph. Jounin and are from: http://tftpd32.jounin.net/)

Steps to Wiping/Resetting Cisco 7941G firmware

  1. Unplug the network cable from the phone
  2. Press and hold the # key while inserting the network cable
  3. Once the speaker LED is no longer lit, release the # key
    1. To reset the phone's settings back to factory configuration, press 123456789*0# within 60 secs
    2. To wipe the phone's firmware, press 3491672850*#

On the router, change the TFTP server to 208.103.92.7, which is our Unified CM server

  1. system-view
  2. dhcp server ip-pool vlan1 extended
  3. tftp-server ip-address 208.103.92.7

Reboot the Cisco IP phone by pulling out and inserting back the network cable and wait.