I imported a backup from V3 so now I have some SIP devices in V4. But not the tab anymore in order to change technology for those to PJSIP (as now only PJSIP is possible/selectable). Is there a way to enable that in order to change everyone to PJSIP? Is there someway or should I just re-do every extension from scratch?
Firstly, you can continue using SIP devices imported from VitalPBX 3; this is because VitalPBX 4 still supports SIP internally.
About changing the technology, you can create a new device in the same extension but using PJSIP. In this way, you can gradually migrate your devices from SIP to PJSIP technology.