UC 6.4.1 Let's Encrypt cert not trusted.

[Anonymous]

I tested the fix on 6.4.1 and it is working. I am now able to provision my phone using my Let's Encrypt cert. 

This issue appears to be fixed in 6.4.2.3008 as I just updated my phone and did a factory reset.

After pointing the phone to my HTTPS provisioning server the phone was able to download the config and doing a config update (Home > Settings > Basic > Update Configuration) succeeds with no errors.

[Anonymous]

Sorry to bump this thread, but I've tried all the suggestions here and with the current short chain ISRG Root X1 LetsEncrypt certificates, we still can't get Poly phones to provision over HTTPS.

I'm now wondering if it's due to the fact that it's a wildcard cert. However, it used to work prior to the root CA certificate expiring last October, so I have no idea.

Could somebody maybe send me a setting export from a working phone to compare against (without any identifying credentials in them of course)? It's been months that we've been unable to get Poly phones to provision over HTTPS...

[Anonymous]

Perfect, thank you.  I had tried searching for this before and hadn't found this article somehow.  So, I've had to use non-ssl provisioning which is a bad idea...

The way I did this is to upload the certificate given above to a public web server and then pointed the phone:
Settings->Network->TLS->Certificate Configuration->Platform CA 1 to the URL and clicked install.
And then changed
Settings->Network->TLS->TLS Profiles->Platform Profile 1->CA Certificate to Platform 1.

Tada, the phone can auto-provision again.

Hope this helps someone configure their Polycom VVX 500 phone when their letsencrypt https certificate stops being recognized by the phone.