5.5. Transferring Calls - Voice-Only and Integrated Configurations 
A call (received via OpenScape Voice) that is currently in progress on your Wi-Fi device, desk phone, or cell phone can be transferred to either someone you have recently talked to, someone on your Contacts list, or a number you enter from the Dialpad. The second party is held during the transfer to the third party.
INFO:
For Integrated Configuration: call transfer works with a Wi-Fi connection. This feature
is not available when connected via cellular data connection.
The control of the call is lost once the transfer is successful. If the transfer fails
(e.g., the
destination is busy, unreachable, etc.), the previous device is recalled.
INFO:
If your transfer fails to a destination that has OpenScape Mobile Pro, it’s likely
that your
Transfer Recall Timer needs to be increased because it’s overriding the
OpenScape Mobile Pro routing timer. In this case, contact your System
Administrator.
‣ Parent topic: Section 5. Handling Calls