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Course Content - Intermediate 2.1

Extension Settings


Welcome to the online training series from 3CX. This module will take you through the various settings which are available for an extension.


By the end of this module, we will have seen the various settings which are available, and possible for the user extensions.

We will go over the general Settings of an extension.

We will see what webmeeting parameters can be configured to allow people to contact you via WebMeeting.

We will talk about the forwarding rules, which will allow you to forward calls when you are not able to answer your calls.

We will go through the voicemail parameters and how voicemail is managed.

We will see the BLF configuration and how you can assign BLFs to an extension very easily.

We will also see the various other options which are available, such as restrictions which can be applied to an extension.


Let's start with the General settings of the extension.

The “General” tab of the extension will contain the personal information of the user of the extension. This will include the mobile number of the user, which will be used when the mobile phone is rung simultaneously with the extension.

The outbound caller ID of the extension, is the number which will be shown to anyone being called over the PSTN from this extension, can be defined in this section as well.

A Direct Inward Dial number is a number which is used to contact an extension within the PBX directly. This was covered in Module 1.4 SIP Trunks. You can also assign a DID directly to an extension from within the extension itself. This will automatically populate an inbound rule and point the call to this extension.


3CX Webmeeting can also be configured to allow people to contact extensions directly.

By leveraging WebRTC technology and using a Google Chrome or Mozilla Firefox browser extensions can be contacted directly. Nothing else is needed from the caller!

With Webmeeting you can have multipoint video where one person can stream video and audio to multiple people, exactly like we do in our 3CX Live Webinars.

You also have the ability to share documents with other participants, allowing you to have a remote web conference with other people without the need for travel. You can also share your desktop so you can give a demonstration or show anything from your computer.

Another functionality of 3CX Webmeeting is that it allows you to offer remote assistance to a caller. All they need to do is request this from within the meeting. Without hassle and without needing to install any other application or extra licenses.


To get  3CX Webmeeting to work with the extension, you will need to create an easy to remember, descriptive URL name. For example “extensionuser”. This will identify to the caller where they are calling, and will also assign the URL to your extension.

Choose the operation mode of Webmeeting you require, whether to connect everyone who calls to a common room. This will require that the person being called is already in a webmeeting room. Or you can opt to have a separate room for each requestor, basically the callers calling from a web browser.

You can now distribute this URL, either through an email signature or on your business cards, making it easy for people to locate you. Whenever someone connects to the webmeeting room of the extension, the extension user will be notified by a chat message in their 3CX client and an email message. Receiving an email is particularly useful for people who do not have a 3CX client and only use a desktop IP Phone, but have access to a computer.


Moving on to one of the oldest PBX functionalities, voicemail. 3CX provides one mailbox per extension. This is included in all licenses of 3CX.

The voicemail system is multilingual and you can choose a different language for each of the users’ voicemail boxes. So, a French user can have a French mailbox prompt, and a German user can have a German mailbox prompt.

A user can customise their greeting, allowing them to have a more personalised message. This can be recorded from the management console from the Voicemail tab, from the 3CX Clients or by logging in to the voicemail menu from an IP Phone.

The email notifications can be configured from this tab as well. This is dependent on an email address being configured for this extension.

The different email notifications for the voicemail can be:

  • Just an indication on the telephone, via the Message Waiting Indicator.
  • An email notification alerting to the presence of a voicemail message.
  • An email notification alerting to a voicemail, with the voicemail audio file attached to the message.
  • An email notification alerting to a voicemail, with the voicemail audio file attached to the message and subsequently deleting the voicemail from the PBX. This can have a beneficial effect on the PBX, as it will lower the backup size of a PBX as the voicemail messages are offloaded to the mail server and mail clients.

It is now also possible, to receive a written transcript of the voicemail contents, via the notification email, as well as the 3CX Web Client.


3CX provides you with the ability to upload a pre-recorded message to be used as a replacement of the default voicemail greeting. The recordings will need to be in the supported audio format, which is a WAV file, encoded in the following format: PCM, 8kHz, 16bit, Mono.

The voicemail greetings can also be recorded from one of the provisioned phones of the PBX. You will have the option to use the recorded greeting for all extension profiles, or a different greeting per forwarding profile.

This will allow you to define a more personalised message depending on the time of the day.

For example:

In the Available status, you can have “Thank you for calling. I’m not at my desk at the moment, so please leave your message, and I will get back to you as soon as I’m back”

In the Away status, you can have “Thank you for calling me. I’m out to lunch at the moment. Please leave a message and I will get back to you”

In the Do not Disturb status you can have the following message “Thank you for calling me. I’m out of the office at the moment. Please leave a message and I will get back to you as soon as I am back in the office”


The voicemail transcript feature uses Microsoft’s Bing SPeech APi to decode and transcribe the voicemail contents. This is globally enabled for all extensions configured in a Pro or Enterprise PBX.

The transcribed text can be seen in the email notification, when this is used, as well as in the 3CX Web Client.


Speaking of the different statuses of the PBX, there are 5 profiles which can be configured with different forwarding rules.

These are:

  • Available
  • Away
  • Do not Disturb
  • Custom 1. This is a replica of the Available status. This, however does not have the auto switching capabilities.
  • Custom 2. This is a replica of the Do not Disturb status. This, however does not have the auto switching capabilities.

The Custom 1 and Custom 2 statuses are customisable per extension. You can change the name of these to suit the needs for each extension.

The different forwarding rules will alter the call behaviour for incoming calls to the configured extension.

From within the forwarding rules, you can choose which voicemail greeting will apply to each of the profiles.

[SLIDE 10]

We will now see the behaviour a call will have, when an extension is in the Available or Custom 1 profile status.

A call routed directly to the extension will ring for a specified timeout, which is also configurable in the forwarding rules, and will then get forwarded to the configured destination.

A call will be immediately redirected when the extension is busy or unregistered.

From the Available status of the extensions’ forwarding rules you can also configure the option to accept multiple calls. Please note that this option does not apply to calls the extension receives via a Ring Group or Queue. The forwarding rule configuration is only valid for direct calls to the extension.

[SLIDE 11]

We will now see the behaviour of an extension when it is in the Away, Do not Disturb and Custom 2 profile statuses.

Extensions in these states will have their calls immediately forwarded. You will have the option to forward calls of internal origin and external origin differently.

[SLIDE 12]

There are a variety of ways which the profiles of an extension can be changed.

The first and easiest way is to use the 3CX Client. A simple drop down box allows you to select the forwarding profile you wish. You will also be able to configure the forwarding rules for each extension directly from the client, without the need to log in to the Management Console.

You will also be able to change the profile state, and Edit your forwarding presets from the 3CX Web Client.

You can use dial codes from any extension which is provisioned on the PBX, to change its own status. The dial code to change the status of an extension is *3 by default.

You will then choose the relevant status.

0 corresponds to Available

1 corresponds to Away

2 corresponds to Do not Disturb

3 corresponds to the custom profile status number 1

4 corresponds to the custom profile status number 2

If your IP Phone has a DND button, you can activate the Do not Disturb profile status using this button. Pressing it again will activate the Available profile status.

An extension can also switch its profile status automatically based on the time of day. This will be covered more extensively in Module, 2.4 Time Based Scheduling.

You can switch the profile status of an extension from the 3CX Management Console, which will also allow you to change the status of any extension on the PBX, depending on the access rights which you may have. This access is given from the Rights tab of the extension. Module 2.2 Extension Groups and Rights covers the details of this particular tab.

By configuring a relevant “Change Status” BLF for each profile, you can choose each status as and when needed, with just the push of a button on your IP Phone.

Another final way of being able to change your profile state is from within the voicemail menu. Log in to the voicemail menu, and in the options you will hear the options which will allow you to change your profile status.

[SLIDE 13]

Forwarding rules are not triggered in some cases.

Whenever a call is received through a queue or ring group, the forwarding rules will not be followed if any of the following parameters are in place.

The destination is configured as “End Call, that is, to terminate the call and if the call forwards to any other auto answering extension, for example another queue or digital receptionist, or if it forwards to any other user or system extension.

In all these cases, the extension will ring normally and not get forwarded based on the forwarding rules.

[SLIDE 14]

We mentioned earlier about the BLF keys which you can configure to change the status of an extension.

BLF means Busy Lamp Field. This basically allows you to monitor the call state of an extension. A BLF on an IP Phone will NOT monitor the profile status of an extension, just the call state. If you configure a BLF on the 3CX Client for Windows however, it will monitor both the call state AND the profile status of an extension.

The different call states which are possible are:

Idle. The monitored extension is idle and not in a call

Ringing. The monitored extension is in the ringing state.

In Call. The monitored extension is in an active call at the moment.

BLF keys can also be used for a variety of other functions.

Apart from monitoring the extension, you can press a BLF which is in the Ringing state to pickup a ringing call of the extension which you are monitoring.

Also, transferring a call to the monitored extension is possible with just a press of the BLF button. You can also dial this extension by just pressing the BLF button.

[SLIDE 15]

A BLF key can also be programmed to perform a variety of other functionalities. In addition to  monitoring an extension, you can program a BLF key in the following ways:

As mentioned a few slides back, you can program a BLF to change the profile status of an extension. Each profile will have its own BLF key.

When an extension is a member of a queue, it can log in and out of the queues. An agent will be able to press a BLF to log in to a queue and another BLF to log out of a queue.

There are some cases where you might not want to monitor an extension, but will just need a speed dial button, to dial this extension quickly and easily. Configuring a Speed Dial button will achieve this.

The PBX also provides the capability to create a custom speed dial, where you will be able to add speed dial buttons for numbers which are outside of the corporation, for example, a home phone number, a supplier or customer.

BLF keys can also be configured as Shared Parking slots, allowing you to park calls. When a call is parked in the shared parking slots, it will light up the BLF key on all extensions configured with this Shared Parking slot configured, allowing the person who parked the call or any other extension with the same shared parking slot configured ,to see the parked call and pick it up. A total of 250 Shared Parking slots can be configured.

[SLIDE 16]

If the PBX is using a PRO or Enterprise Edition license key, users can configure their own BLF keys, without the intervention of the PBX Administrator.

This is achieved through the 3CX Client for Windows. Expand the BLF side panel, from the menu of the client. This is activated by clicking the 3 Blue dots in the top right. You will now see the BLF panel, with any BLFs which may already be configured. Right click a BLF key and click configure. Configure the BLF with whatever BLF feature is required.

This configuration will apply to all the devices which are provisioned on that extension, including logged in Hot desk extensions. 3CX clients will automatically and immediately have these available to them. IP Phones will either need to be re-provisioned, or, will apply with a delay of 24 hours when they automatically re-provision.

[SLIDE 17]

From the extension’s Option tab, you can impose restrictions on the extension to define some functionality and security.

When an extension’s user goes on extended leave, you can disable this extension so it will not be used maliciously. This is especially useful in open plan offices.

Alternatively, you may not want to disable the extension entirely, but only external calls which may incur a charge. This will allow the extension to make calls to internal extensions, queues, ring groups or digital receptionists but not to external numbers.

Another blocking functionality is being able to PIN protect the extension. This will require the extension to call the PIN Protect Digital Receptionist, authenticate with the Voicemail PIN Number and then be able to make a call within a predefined timeout. More about this is mentioned in module 3.4 Digital Receptionists.

When an extension is only required to provision and connect to the PBX from within the local LAN, there is no need for it to be allowed to connect from outside of the LAN. The “Disallow use of extension outside the LAN” option will prevent any attempts to provision this extension from outside the LAN. Please note that this will not prevent any 3CX clients or SBC extensions from connecting. This is only for remote STUN extensions.

You can block SBC extensions or 3CX clients from connecting, by enabling the “Block Remote Tunnel Connections” option.

Another blocking functionality which can be configured on the extension is the option to block outbound calls from this extension, outside office hours. This is quite handy, again in an open plan environment, where you can make calls during the working day without restriction, but when the phone is not in use at night, outgoing calls are restricted. This is helpful as it can prevent malicious use by anyone not authorised, when the phone and desk are not being used.

[SLIDE 18]

 An extension user can receive an email notification for any missed calls to their extension. This assumes that a valid email address is configured on the extension and that the SMTP server is setup correctly and has been tested.

3CX provides the ability to hide the extension from the company phonebook, so the contact information of the extension is not shown in the phonebook. This will not prevent the extension from showing in the presence screen. This is defined from the Rights tab of the extension and is covered in Module 2.2 - Extension Groups and Rights.

The ability to allow an extension to login to a hot desk device is also done from this tab.

When a call is forwarded to an external location, the person answering has the option to filter the calls being accepted based on the callers caller ID, with a functionality we call Rebound. However, sometimes, if someone calls from an unknown number, having the caller ID read out to you is pretty unintuitive. To get over this, you can request the caller's name so that you can filter the person before answering.

[SLIDE 19]

Call recordings on the PBX, are done at an extension level, and in the options tab you can enable the recordings for the extension.

There are 3 levels of recording possible.

Off, which does not log any calls to the extension by default

Record all calls, which will start the recording by default for all calls placed or received by the extension

Record External Calls Only will only record calls made or received by the extension, from an external location, that is, a provider or gateway, and not from another extension.

If the PBX is an Enterprise Edition PBX, you will also be able to prevent an extension user from either starting or stopping a recording, and they will be forced to use the default setting which is defined on the PBX.

[SLIDE 20]

Thank you, and goodbye!