My Lync environment at the house has been set up to support an old LG-Nortel IP8540 – Codenamed “Tanjay”. I got this device when OCS was still in beta, but never did anything with it. At the time my company was not interested in the IP phones and all the hoopla to set it up (i.e. DHCP options, etc.). This thing collected dust for almost 5 years. Last spring I pulled it out and was able to upgrade it from the beta code (v 1.0.199) it was running to version 4.0.7577.4066 (1.23). Jeff Schertz has a good blog on the subject, so I will not cover that here.

When I tried to install a Polycom CX500 I ran into a couple of errors. Here is what I found. When I plugged the phone in to the network and tried to login I receive an error “Certificate web service cannot be found.” My IP8540 is working fine. Why can’t the CX500 contact Lync. The word certificate made me think there was an error with certificates, but it turns out it was a DHCP issue.

1. Plug in the phone to the network and power cord (or use Power over Ethernet).

2. When the phone boots up it will prompt you to push a button to continue. An odd step if you ask me.

3. Next you will be asked to “Enter your extension or phone number”
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4. The next screen prompts you to “Enter your PIN for xxxxxxxxxxx”. One thing to note, that I didn’t realize at first was that this is asking for your Dial-in Conferencing PIN. I was trying to use my unlock PIN from the IP8540. If you’re set up a device unlock PIN on another device (ex. IP-8540/CX700), then this step will fail. If you don’t know your Dial-in conferencing PIN then you can reset it at
Once you know this PIN enter it here to login.
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5. In my environment I received the following error: “Certificate web service cannot be found. Please contact your support team.”

As I mentioned, the DHCP options that you set up for the IP-8540/CX700 are not valid for the CX500. You need to enable DHCP options built in to Lync. You don’t need to remove the DHCP options on your DHCP server to make this work, but I have read a couple of articles that say you should. I’ll test this later.

To enable the DHCP options in Lync, run the following cmdlet:

Set-CsRegistrarConfiguration –EnableDHCPServer $true

After you reboot the phone, you go back through the login steps and you should be in business.

CX500-1CX500-2photo 1photo 2CX500-3CX500-4CX500-6CX500-7CX500-8CX500-9CX50010CX50011CX50012CX50013CX50014CX50015