Grandstream GXP1780 Transfer call


I have to forward calls on the Grandstream GXP1780. Although I followed all the steps in the guide, it does not work. What can I do?


Forward is supported by Server. If you have direct line from provider then contact them and ask fro advice.


Hard to provide a good answer without more info.
We don’t know anything about your provider or what your phone is connected to.

Can you offer any more information about the phone system?


We are from Germany and of course we have a German provider. I need to forward calls to another device, so I try to follow the described steps in the guide book. When a call comes in, I press the “forward” button (the sign with 2 phones), dial a number and then press “transfer” (shown right on the phone screen).
Anyway, I tried several ways to forward calls, but it never worked.


How many call paths does the provider support in this instance?


You want:


This are 2 different types and function.
Transfer is fro active call, forward is for incoming not responded call. Which one ?


I want to transfer active calls.


Blind or attended not work ?


We need a solution for active and passive calls. Mainly passive calls to the landline office number.

Call Transfer

GXP17xx Blind Transfer, Attended Transfer and Auto-Attended Transfer.

 Blind Transfer.

 During the first active call, press TRANSFER and dial the number to transfer to. OK
 Press SEND key or # to complete transfer of active call. Line 1 changes from “TALKING” to “TRANSFERRING” for 1 second, then changes back to “TALKING” – nothing happens, the active call is being resumed

 Attended Transfer.

 During the first active call, press LINE key. The first call will be put on hold.
 Enter the number for the second call in the new line and establish the call. Does not work for other landline numbers in the same network. The call can’t be established. It rings 2 times, then it says “the recipient is not available”.
 Press the other LINE key which is on hold to transfer the call. This method works perfectly for any other numbers outside of the office network. But we require to transfer calls to other phones within the same network



First change this option Settings -> Call Features

Now Blind transfer:
Get call, press TRASFER button, put new number and again TRANSFER.

As for attended - talk with VOIP provider, this is limitation from them. Phones do not care what number you put.


Thank you.

There is no attended Transfer Mode in the “Settings -> Call Features” option that I can change.
When I open the option “CALL FEATURES”, there is a list of our office numbers coming up:

Blind transfer:
Got a call, pressed TRANSFER, put a new number and then again TRANSFER => nothing happened.

TRANSFERING CALL works if I transfer the active call to any number, except our office number.


Last sentece mean: go ask provider, there is something wrong there.

As for option: you have old FW ? it is in GXP17xx
Also it is not under ACCOUNT.