Cisco Support Community
Showing results for 
Search instead for 
Did you mean: 
Community Member

First Line Freezes

I have CISCO 7940s and 7960s deployed over a site. When a call comes thru on the 1st line of a 7940, the user answers the call. During this process if there is another call which comes to the same number, which gets rolled over to the second line, the first call gets frozen.

Unless some one else picks up the second line, the user is unable to do anything with the first call.

This is the first time I have encountered this issue.

Would any one be able to shed some light on why this is happening and how it could be rectified.

Community Member

Re: First Line Freezes

Take a look at this document it may help:

If not, let us know what ver of CM and phone load you are running.

Community Member

Re: First Line Freezes

Thanks for the link to the document. But for some unknown reason, I am unable to view or to this link to getthe document.

Even though I have registered with, I am having this issue.

Would appreciate if you could e-mail it to me.

Community Member

Re: First Line Freezes

You need CCO access to view it.

Here's basically what it says. Let me know if it helps.

Problem Overview

With the current implementation, an IP phone can only handle two calls per line. When you transfer a call, the phone will actually first initiate a new call to the transfer-to phone and then transfer the first call. This means that with every transfer there will be two active calls on the line.

When call waiting is enabled, an IP Phone is able to accept two incoming calls on one line. Because of the above requirement, you will not be able to transfer any of those calls. This would require another line instance to initiate the additional call towards the transfer-to party.

Step-by-Step Solutions

When there is more than one line on an IP phone, the solution is to disable call waiting and configure the first line with Call Forward Busy to the next line.

If there is only one line on the IP phone, you can also disable call waiting. However, in that case it will only be possible to receive one incoming call and a second incoming call will be transferred to the Call Forward Busy extension configured for that line.

Community Member

Re: First Line Freezes

Thanks Anwar.

As a matter of fact I do have access to CCO. Otherwise I will not be able to view and post to the forums.

I do have another question. Have you got to do it globally from the call manager or has it got to be done on individual phones? I think this happens on certain phones only.

Community Member

Re: First Line Freezes

You can either disable it on individual phones or system wide. This explains how to do either:

Option 1: Disabling Call Waiting for a Specific Line

Go to the Directory Number Configuration of the IP phone. Look for the parameter called "Call Waiting".

From the drop down menu select Off. Click Update and restart the device.

Option 2: Disabling Call Waiting System Wide

Note: If you disable Call Waiting system wide, all IP phones will be affected, unless otherwise configured on specific lines.

Go to the Service Parameters for the service "CallManager". Look for the parameter called "CallWaitingEnable".

From the drop down menu select False and the update.

Community Member

Re: First Line Freezes

Thanks a lot Anwar.

I have also posted another in the same forum on the Auto Registered phone not being able to manually register with an extension.

Would appreciate if you could take a look at it and get me some help.

CreatePlease to create content