Hello, I configured the SIP TLS on my 3CX configuration, the 3CXPhone for Windows connects to 3CX IPBX without issue, the connection is totlaly secure. The issue is for the 3CXPhone for MAC OS, i installed the root.crt and cert in folder 3CXPhone/Certificates the software connects to IPBX without problem with secure connection but when i call an extension the error appears and the connection hangs up at 32 secunds : LOG : 21:00:50.640 PjsuaCallbacks TLS certificate verification result of [10.10.10.38:5061]: 21:00:50.640 pjsua_acc.c Disconnected notification for transport tlsc0x7facaaa22e28 21:00:50.640 tlsc0x7facaaa2 TLS connect() error: SSL certificate verification error (PJSIP_TLS_ECERTVERIF) Code: 21:00:50.640 tsx0x7facaaa2a Failed to send Request msg BYE/cseq=12922 (tdta0x7facaaa29600)! err=171173 (SSL certificate verification error (PJSIP_TLS_ECERTVERIF)) In fact the software tries to connect to private IP while i use it in external context so i don't know why it doesn't tries to connect to Public FQDN. I changed the software configuration : Local IPBX with th FQDN but same problem. Maybe a bug with the 3CXPhone for MAC OS ? Since four days i search :( can you help me :D ?