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How to install 3CX Phone System

What is 3CX?:

3CX is a software based PBX (Private Branch Exchange) based on the SIP Standard which enables users to make phone calls internally and externally via PSTN (Public Switched Telephone Network) or VoIP (Voice over Internet Protocol)

Prior to the installation, please verify that your system has the following: Please note that these are the minimum requirements to run the PBX, but additional requirements may be needed for call recording.

If you would like more information on hardware requirements please click here for a full list

  • Windows (Standard or Server) – Must be x64 Bit Architecture
        -Standard Windows – Windows 7 or Higher
        -Server Windows – Windows Server 2008 R2 or Higher (GUI only)
  • .NET Framework version 4
  • Atleast 1GB RAM
  • Atleast 3.2 GHz Processor
  • Atleast 30GB Free space on your hard drive.

If you are installing 3CX Phone System on a Virtual Machine there are additional requirements:

  • Static MAC Address
  • Integrated Services

For more information on requirements for a Virtual Installation please click here for a full list


  • It is recommended to make this a dedicated server for only 3CX as it uses a lot of memory and resources
  • Internet Explorer, Firefox, or Chrome
  • 3CX Supported VoIP Phones & Gateways
  • 3CX Supported VoIP Providers & SIP Trunks
  • Static port mappings / Port forwarding
  • Static public IP address
  • Installing 3CX Phone System on a machine that also has the following products installed – Microsoft Exchange Server, SQL Server, SharePoint or DNS Role is not supported.

After verifying you have the required software and hardware, you can proceed with the installation of 3CX.

The first screen you will see when launching the executable installation file will be the requirements and recommendations that are listed above. Press Next to both of these screens after confirming you have the proper software and hardware components required.

The next screen that will be displayed is the End-User License Agreement. After reading through the terms, please select the options on whether or not you accept the terms. If you do not accept the terms within the License Agreement you will not be able to proceed with the installation.

You will then need to select the directory in which you would like to install 3CX. The default location for this is going to be on your main hard drive within the Program Files folder. You can change the default location by selecting Browse.

After selecting where you would like to install 3CX Software, you will now be prompted on whether you would like to have a standard installation or a virtual installation.

  • Standard Installation
        -This option will be the only available option if you are running a Standard Windows Operating System(Non-Server)
  • Virtual PBX Installation
        -Only available on Windows Server machines
        -Allows the server to accept up to 25 instances of 3CX on one server

If you are installing 3CX on a server behind a NAT, you will have to configure port forwarding to allow traffic to come through to your server and be able to communicate with 3CX properly. If your server is not behind a NAT, you will not need to do additional port forwarding but still may need to verify that your firewall is not blocking any incoming and outgoing traffic. If you are unsure of which option applies to your setup, please contact your network administrators for more information

If you select No NAT you will be presented with the next screen only asking for the default network interface. This is a drop down menu which allows you to select the proper IP address if you have more than one Network Interface Card.

If you selected the option that you are behind a NAT then you will have to select both the Default Network Card as well as the Static External (public) IP Address.

After configuring the NAT and IP settings, you will be prompted for an administration email address. You will be notified by email when any updates are available as well as any system notifications such as outages or service failure.


The next step of the 3CX installer will prompt you whether you would like to use:

  • Single FQDN
        -May require split DNS
        -May require Dedicated Domain
        -Only needs a single address
  • External/Local FQDN
        -Needs multiple addresses
        -May require a domain
  • Local IP address
        -This limits 3CX for internal use only.

FQDN – Fully Qualified Domain Name

  • A Fully Qualified Domain Name allows you to have several services running on sub-domains. For example, a mail server may be set up using, pointing to one IP address while a website may be set up under, pointing to another IP address. Fully Qualified Domain Names allow different sub domains to route to different IP addresses allowing other services to run on the same hostname.

Split DNS (Domain Name Server) – creates two DNS zones – one DNS for internal domain name resolution, one DNS for external domain name resolution. In order to set up Split DNS, a dedicated Domain is required.

The next section, you will need to fill out the information depending on which choice you selected:

  • Single FQDN
        -Needs only one FQDN
  • External and Local FQDN
        -Needs two FQDNs, one External / Public Domain, and one Internal Domain or Private IP Address
  • Local IP
        -This will allow you to only use your Private IP and Public IP address as the Internal FQDN, making this only available for internal users

The next step in the installation is setting up outgoing emails. This will be used for any notifications / service failures. You will need to know your Mail Server, your email / reply address, the username that is used to login to email and the password for the account. You then have the option to enable secure messages (SSL/TLS). Please verify with your email administrator that you have SSL/TLS enabled before proceeding.

3CX Web Management Console allows you to update settings and features through your internet browser. In order to use this administrative console you need to set up a username and password. This information can be changed through the Management Console

In order for the Web Management Console as well as other services to work properly, you need to configure a webserver. The two options that are provided are 3CX Web Server (Abyss Web Server) or Microsoft IIS (Internet Information Service). Abyss will be the only option available if you are installing this on a Standard Windows (Non-Server). IIS is the preferred web server as it is native to the Windows Server Operating System and other services may already be using IIS.

Prior to selecting which Web Server you would prefer to use, please verify with your network administrators that nothing is already running on the selected ports or it may cause conflicts and neither application will work. Abyss will allow you to select different port numbers such as 5000(HTTP) and 5001(HTTPS), as seen below. Please note that if you change the ports within Abyss you will not be able to alter this after the installation. IIS will select the web server ports which is 80 (HTTP) and 443 (HTTPS) and will not provide an option to change these ports. If you use IIS please verify that your HTTP (80) and HTTPS (443) ports are not being used by another application or service within the same domain.

In order to use the HTTPS port, a SSL Certificate is needed. SSL certificates allow secure communication between web servers and encrypt information to protect data. This encryption is a requirement on 3CX Web Console. If you already have an SSL Certificate you can import it – but if you do not already have a certificate you can have 3CX installer generate a certificate. Keep in mind, if you select this option it will give security warnings to anyone who will access the webpage.

If you selected the option to generate a certificate you will be prompted for you company name as well as a password for your certificate. Please enter this information and press Next to continue with the installation

The next screen will show you all of the information for the installation as well as give you the option to change any settings by pressing the Back button. If you are content with your options, you can select Install and the process can take several minutes depending on your hardware specifications

After the installation you will have an icon on your desktop. By opening this application, it will open a web address in your default web browser and may take several minutes to load the web page.

The Icon that is on your desktop should look similar to this:

After the webpage loads, you will be prompted with a username and a password which was set up during the installation process. Please enter the information and login with your credentials

After you are logged into the web management console you will be prompted to set up the number of digits for internal extensions. By default this option is set to 3 digits. Please note that you will not be able to change this setting after the installation is complete. In order to change the extension length a fresh install will need to be performed (uninstalling 3CX and reinstalling). Please note that if you decide to change the extension from a fresh install, you will not be able to restore from a backup because the extension length will be incorrect.

You will now be prompted with the time zone and country that your 3CX Phone System is operating from.

You will now have to set up an operator extension. This extension is the default destination for inbound calls. Please provide the extension, voicemail extension, their first name, last name, and email address.

After setting up your operator extension you will be able to set up options for international calls. You can use the arrows on the left hand side of the region to expand other options and view more specific regions. By checking additional checkboxes, you will allow outbound phone calls to be made to other countries. Any checkbox that is not selected will disallow any external phone calls to be made to that region, but incoming calls from those regions will still be allowed.

Your set up is now complete and you should see a screen similar to the image below – you will also have a quick start guide on the next steps to complete your 3CX Server.


Choose files or drag and drop files
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  1. Steve Stoveld

  2. Posted
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