Thank you. We have some T42G's experiencing this. I will await a fix from you and follow the above thread.Hi @Matt_Alcom_IT,
This would be related to https://www.3cx.com/community/threads/certificate-error-yealink.84628/
Yes, all is working fine thank you.This issue has now been resolved: https://www.3cx.com/blog/releases/lets-encrypt-expiration/
Please install the Hotfix if you haven't already done so, and let us know if your phonebook downloads now.
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