I just can't get autoprovision to work on remote (stun) connected phones. This is not good given 3CX are actively pushing "host us on cloud servers" now! Here's the setup:- 3CX v15 Linux edition running on a Google ComputEngine server. Yealink T42, T40, or T27 phones. No SBC (we will be putting one in for some customers, but the main reason I'm setting THIS particular server up is to offer single extensions to "work from home" type customers, so no SBC should be required) I'm creating the extension, then adding the appropriate model phone in Provisioning. Cut'n'paste the MAC address from the phone GUI into the Provision Phone. Set it up "Direct SIP (STUN) Remote", at which point 3CX automaticallt selects the WAN i/f. The 3cx screen also presents at this point the provisioning URL, which I copy and paste into the Server URL field on the "Autoprovisioning" page of the phone. I am remembering to untick the "lan only" permission for the extension. Then I try clicking the "Autoprovision Now" button, and the phone says it's done it. But it hasn't. I've tried rebooting the phone, it's supposed to auto-provision on reboot. But it doesn't. I've tried going away and doing something else and giving it time. But it doesn't. I called 3CX support. They talked me through turning off the "Only Accept Trusted Certificates" option in the Security Tab. And that worked. For one day and two phones only! Now I'm trying it again on a new phone with that option already selected, and it doesn't work. ONE TIME the PBX log says its' been asked for and has sent the config, but, the phone didn't get it. I've checked the phone isn't getting itself blacklisted. I'm utterly at a loss. I can't see why it works one day and not the next. And frankly unless I can make it work reliably, every time, it's not really something I can put in front of a customer!!