Cisco 7962 SIP Phone Shows Old Caller Names on Idle Screen Even After Clearing Missed Calls

Asterisk Asterisk Endpoints
1

Hello,

I am using a Cisco 7962 with SIP firmware registered to Asterisk/Issabel.
I have a strange issue with the phone’s idle screen:

Problem

Whenever I receive an inbound call (answered or missed), the caller name or CID stays permanently on the idle screen of the Cisco phone, for example:

From Taabodi-Steel
From 114
From Dastbaseteh

These entries remain visible even after I clear the Missed Calls list on the phone.
However:

  • After rebooting the phone, the entries disappear.

  • Pressing the CFwdAll softkey also clears them, but only temporarily.

  • Directories → Missed Calls is completely empty.

The phone is receiving no BLF, no XML idleURL, and no directoryURL.
I also confirmed that <callLogBlfEnabled> is off.

2

On Tuesday 25 November 2025 at 13:46:02, shbruzu via Asterisk Community wrote:

I am using a Cisco 7962 with SIP firmware registered to
Asterisk/Issabel. I have a strange issue with the phone’s idle screen:

I find it hard to discover anything in this question which is about Asterisk.

You might be lucky and find that someone here has used that type of phone,
but in general the opinion here (including my own) appears to be “avoid Cisco,
they’re non-standard (even when they claim to be running SIP firmware)”.

Sorry,

Antony.

–
You can tell that the day just isn’t going right when you find yourself using
the telephone before the toilet.

3

I have several of these older Cisco phones in my test lab, a 7940, 7960, & 7961. Unfortunately, I do not have a 7962. The problem you are describing does not appear on any of my 79xx series test lab phones.

I have posted extensively on the FreePBX forums on use of these phones so you may find more information there. But, as far as the 79xx series is concerned:

These phones are pretty extensively documented all over the Internet due to one fact, that is that “back in the day” in the heady days a generation ago of early VoIP - there were TONS of them sold. Because of this they were readily available on the used market and with their large generous screen they allowed plenty of space for custom applications. The fact that they were also product-placed in the TV show “The Office” which was very popular, didn’t hurt either. They are still to this day readily and cheaply available on Fleabay, etc. (and, many times, available free for dumpster diving)

But there are several things to beware of:

  1. Most of them shipped with SCCP firmware and are a royal pain in the keister to upgrade to SIP - even though Cisco did release SIP firmware for them - requiring multiple firmware step updates. Many enterprises discarded them rather than upgrade them so they flooded the used market.

  2. Only the original 7940’s and 7960’s allowed for multiple linekeys with different userIDs/passwords per key - the 7961, 62 and all later versions of the 79xx series shifted to the “callmanager” firmware that either require the USECALLMANAGER patch for this or are restricted to 1 extension # per phone

  3. Only recent versions of chan_pjsip will connect to these phones, older versions require an addition to the pjsip config file per extension.

  4. All of the 79xx series have many weird bugs in different firmware versions that are model-specific. Meaning, that for example version 9.4.2 firmware for the 7961 acts differently than version 9.4.2 for the 7962 For example, your “persistent caller info” is obviously a bug, you should attempt updating firmware.

  5. Cisco pulled all old phone firmware around 2022 off their website. You can still find the documentation for much of this firmware but not the files themselves. For example for the 7962:

Cisco Unified IP Phone 7942G/7962G Firmware Load 9.4(2) SIP

is the readme. The actual firmware itself can still be found in odd places on the Internet, such as the following:

lrcamargo/cisco-ip-phone-sip: Configuração para telefone ip cisco usando SIP e Asterisk/Freepbx

  1. These must be configured with a TFTP server and SEPMAC config file. These files are not trivial to understand. They are not documented by Cisco because the UCM generates these on the fly by querying it’s phone provisioning database. And nowadays they are all encrypted so it’s no longer possible to extract them from a UCM so most of them out in the wild are copies of others out in the wild by people who don’t understand them.

  2. The plastic Cisco used to make these phones was pretty inferior and age-embrittles so treat them gently.

It is much cheaper and easier nowadays to look on Ebay for a used 3PCC phone if you must have a Cisco device, you can find them for under $50, and provisioning instructions are here: