User manual

15. Q: Why do Yealink phones use DOB format logo file instead of popular BMP, JPG and so
on?
A: The picture the phone can recognize has some special requirements. It is not easy for the
phone to resolve a popular picture format such as BMP and JPG. To make it easy, we enable
only DOB file. There’s a tool for you to convert a BMP file to DOB file. You can download the
tool and instructions from below link,
How to change the logo of Yealink Phones Rev_61.0
16. Q: How to change the “Yealink” logo on LCD?
A: Please refer to the document:
How to change the logo of Yealink Phones Rev_61.0
17. Q: How to make ringtone for Yealink phone?
A: You can use the Cooledit tool to make the ringtone you like, and upload the ringtone to
the phone. For more details, you can refer to the document for T2 series:
How to Make Ringtone for Yealink SIP-T2XP Phones Rev_61.0
18. Q: Why I can’t send a SMS to any other phone?
A: SMS is a feature that needs your server’s support. Please just check it with your system
manager.
19. Q: How can we reset the phone to default settings?
A: If you can access to the phone by admin, please click to page Upgrade -> Basic, then click
Reset button to reset the phone to factory default.
Or you can press the Menu->Settings->Advanced Settings->Reset to factory through phone
UI to reset the phone to factory default.
20. Q: Why the phone cannot obtain an IP address via DHCP?
A: Please check the connection with the network cable. Make sure the network and the
DHCP server both work fine, and there isn’t more than one DHCP server.
21. Q: What is the mechanism of DHCP?
A: The DHCP mechanism is like below: