I wanted to update my earlier thread with the same title, to advise the resolution. But as that thread is now locked, I am creating this new thread. The text of my message posted to the original thread is included below, after the resolution.
RESOLUTION
It transpired that this particular phone was configured to register via an SBC on a local windows server, which connects to the 3CX system in the cloud. The SBC was installed in 2017, and clicking on the 'updater.exe' file associated with this SBC installation reported that the latest version was already installed. However, it became apparent that this SBC was not connecting to the V18 3CX system (due to error: "3cx" sbc tls handshake failed: error:00000001), and, despite the message reported by updater.exe, I strongly suspected that this version was absolutely NOT the latest. Consequently, I downloaded and installed the latest SBC version which then connected successfully to the 3CX system. Subsequently the Cisco phone was able to register.
So, in summary:
(a) a 480 response is seemingly returned by an SBC when it is unable to connect to a 3CX system. (It was not related to any custom template errors).
(b) its important to check whether there's a new version of the SBC software that needs to be installed when upgrading to a new 3CX release (even though the upgrade documentation may not identify any need to update SBCs!!).
ORIGINAL POSTING DESCRIBING THE PROBLEM
Two years ago, I used the info at https://www.3cx.com/sip-phones/cisco-spa/ to successfully provision a SPA504G phone using a custom template. Subsequently this phone has worked consistently with 3CX version 16.
However, after upgrading to V18, registration failed for each of the phone's four lines and in each case the phone indicated server error code 480 (temporarily unavailable?). Sadly, this has compelled me to revert back to V16, as this phone needs to be operable during office hours.
Before the upgrade to V18 I performed a backup with the "Custom Templates, Logos, Firmwares and Faxes" option checked. I then restored this backup after upgrading to V18. And when
I checked the provisioning directory its contents after the upgrade appeared to be the same as they were prior to the upgrade. Likewise, the content of Management Centre screens appeared to be the same as they were prior to the version upgrade except that the Cisco phone lines (for which registration failed) no longer appeared in the 'Phones' list.
I suspect it's time for me to replace the SPA504G phone with a 3CX supported phone, but I am posting this to see if anyone can offer any obvious cause for this issue or a way of easily diagnosing this issue, bearing in mind that to perform any diagnostics it will be necessary to upgrade to V18 again and then revert back to V16 again if the problem persists.
In particular, does anyone know whether V18 has introduced any required template content changes, particularly in regard to custom templates, or are templates supposed to have the same format for V16 and V18?
RESOLUTION
It transpired that this particular phone was configured to register via an SBC on a local windows server, which connects to the 3CX system in the cloud. The SBC was installed in 2017, and clicking on the 'updater.exe' file associated with this SBC installation reported that the latest version was already installed. However, it became apparent that this SBC was not connecting to the V18 3CX system (due to error: "3cx" sbc tls handshake failed: error:00000001), and, despite the message reported by updater.exe, I strongly suspected that this version was absolutely NOT the latest. Consequently, I downloaded and installed the latest SBC version which then connected successfully to the 3CX system. Subsequently the Cisco phone was able to register.
So, in summary:
(a) a 480 response is seemingly returned by an SBC when it is unable to connect to a 3CX system. (It was not related to any custom template errors).
(b) its important to check whether there's a new version of the SBC software that needs to be installed when upgrading to a new 3CX release (even though the upgrade documentation may not identify any need to update SBCs!!).
ORIGINAL POSTING DESCRIBING THE PROBLEM
Two years ago, I used the info at https://www.3cx.com/sip-phones/cisco-spa/ to successfully provision a SPA504G phone using a custom template. Subsequently this phone has worked consistently with 3CX version 16.
However, after upgrading to V18, registration failed for each of the phone's four lines and in each case the phone indicated server error code 480 (temporarily unavailable?). Sadly, this has compelled me to revert back to V16, as this phone needs to be operable during office hours.
Before the upgrade to V18 I performed a backup with the "Custom Templates, Logos, Firmwares and Faxes" option checked. I then restored this backup after upgrading to V18. And when
I checked the provisioning directory its contents after the upgrade appeared to be the same as they were prior to the upgrade. Likewise, the content of Management Centre screens appeared to be the same as they were prior to the version upgrade except that the Cisco phone lines (for which registration failed) no longer appeared in the 'Phones' list.
I suspect it's time for me to replace the SPA504G phone with a 3CX supported phone, but I am posting this to see if anyone can offer any obvious cause for this issue or a way of easily diagnosing this issue, bearing in mind that to perform any diagnostics it will be necessary to upgrade to V18 again and then revert back to V16 again if the problem persists.
In particular, does anyone know whether V18 has introduced any required template content changes, particularly in regard to custom templates, or are templates supposed to have the same format for V16 and V18?
