Mitel 1000 Owner's Manual page 32

It is possible that an extension may misuse the External Forward
facility. The default setting is that no extension is allowed to set
the facility.
WARNING
When 'Forward when busy' is enabled on an extension to
Forward to an external number, external incoming calls will
Forward but internal calls will not.
Forwarding an external call to an external number ties up two
Note
lines. If your system only has 2 lines, incoming calls will get a
busy signal until the transferred call has cleared. Such calls are
called trunk-to-trunk calls.
To cancel a forward when busy
1. From the Idle Menu, select 'Extension Forward'.
2. Select 'Forward when busy'. The forwarding is
automatically cancelled and the display returns to the Idle
Menu.
To forward calls when your extension does not answer
The 'Forward On No Answer' allows you to forward all your calls to
ring at another extension if there is no answer at your extension
after four rings. Alternatively, you can forward all external calls to an
external number if your extension has not answered after four rings.
In this case, internal calls will not be forwarded but will continue to
ring your extension.
1. From the Idle Menu, press the Scroll Down Key ( ) until '
Extension Forward' is displayed.
2. Select 'Forward on no answer'.
a) Enter an internal number if you want to forward all your
b) Enter 9 followed by an external number if you want to
3. Press 'Confirm' to accept the number.
It is possible that an extension may misuse the external
forwarding facility. The default setting is that no extension is
allowed to set the facility.
WARNING
If 'Forward On No Answer' is enabled on an extension to forward
to an external number, external incoming calls will forward, but
internal calls will not. Forwarding an external call to an external
number ties up two CO lines. Such calls are called trunk-to-trunk
calls
Note
Forwarding an external call to an external number ties up two
lines. If your system only has 2 lines, incoming calls will get a
busy signal until the transferred call has cleared. Such calls are
called trunk-to-trunk calls..
calls to another extension.
Forward external calls to an external number.
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