The 3cx client only displays the extension number, or, if there is an external inbound call it only reports the phone number. It’s really strange. I tried using x-lite instead and it displays the correct caller id for both internal and external calls. Btw, im using the latest version of the client. Also, for testing porpuses, I went to file->preferences->checked notify external program-> I selected notepad with %callid%. In effect, when a call is received it displays the callerid parameter as a number instead of a name, which coincides with the first sentence of the post.