Frequently Asked Question

If your SIP Phone is unresponsive it may have gotten its firmware corrupted. Please follow the instructions below or on the last page of the SIP Quick Reference Guide 3.x - 2024.

You must use the correct update.bin file for your model and then after it is restored it will be restored to version 3.0.0-053...then you can upgrade through the web interface provisioning page or using firmware.cetis.txt via tftp, etc to upgrade again to a higher revision. 

As of September 2024 we recommend revision 3.0.0-077

Firmware prefixes for each model are described below:

SIP Quick Reference 3.x September 2024

Firmware Recovery to Factory Default – 3rd Generation Cetis SIP Phones

If a state arises where the phone will not boot properly, and it appears that the firmware may have been corrupted, it is possible to reload system firmware back on the phone and return it to a factory default state. Download the accompanying 3GEN POST MODE-053.ZIP file and select the correct firmware file update.bin – it will be specific to your model of phone, designated by the prefix (C31, CC1, CD1, etc.) to load on the phone via tftp server.

Open a TFTP server on the PC, place the correct update.bin for your phone in the root directory of the TFTP server. (We recommend Windows freeware tftpd64)

Enter the POST (Power On Self Test) MODE function to prepare the phone for a system restore. This is achieved as per the following steps:

Press # key as you insert power into the phone's WAN port, and release the # key after 5 seconds.

1. Connect phone's WAN port to PoE power and the phone’s LAN port to PC's network port
2. Open the TFTP server on the PC, place the file update.bin in the root directory of TFTP server.
(Open the log tab so you can watch the request and see the sending of the file.)
3. MWI Key Flashes rapidly to indicate POST mode
4. The phone is now in POST MODE and waiting for input command

Press 2 to Restore the System by downloading update.bin firmware from the tftp server

5. When prompted for a server address enter the IP address of your server using the keypad and the * key as the periods between octets and end with a #. 

Example 10 * 40 * 0 * 52 # will try to retrieve the update.bin from the tftp server at IP address 10.40.0.52
7. If the phone SUCCESSFULLY retrieved the update.bin firmware file and applied it, the LCD will display on the screen:

LOAD OK
Update System...
After several minutes, it will change to display
LOAD OK
UPDATE OK

Now the phone's system is restored to version 3.0.0-053 and able to upgrade to a higher version via logging into the web User Interface and upgrading in the provisioning page or alternatively using a tftp server and firmware.cetis.txt. Consult the accompanying SIP Quick Reference document in this FAQ page.