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Skype for Business, IP Phones, Configuration and Installation, Certificate Web Service error

I am trying to install a new IP Phone for UC Voice, but I get a error: Certificate web service cannot be found.

An IP phone is a hardware-based phone for making telephone calls using an Ethernet connection, without requiring a computer to function. 

IP phones need to be plugged into an active network jack that has been enabled for the voice network.  If you wish to use an IP phone, you must work with your department IT Professional (network administrator) for a successful installation.

Within Iris, the Voice VLAN box must be checked for the port/jack that the phone is plugged in to.  If the check box is not available in Iris, then the IT Pro needs to have the Voice VLAN configured on their Switch (

You might have to factory reset the phone. 

Polycom CX500/600/3000 phones: Press and hold the * and # keys, while you power-cycle the phone (disconnect reconnect power), hold keys for approximately 10 seconds. Follow on screen instructions to proceed.

also see: Skype for Business, How to reset IP Phone

Yealink T4x series phones: Press and hold the OK, or Yes key for 5 seconds, then follow onscreen instructions.

Yeaklink T5x and CP960: Press and hold Home button for 20 seconds.

Keywords:Lync IP phone certificate skype for business voice vlan iris, skype for business   Doc ID:34135
Owner:Lync M.Group:University of Illinois Technology Services
Created:2013-10-04 13:27 CDTUpdated:2020-07-14 11:33 CDT
Sites:University of Illinois Technology Services
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