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Installing 3CX on Windows

On this topic

Step 1: Check System Requirements

Supported VM Platforms

Network, Firewall & Other Requirements

Step 2: Prepare Your Host Machine for Installation

Step 3: Install 3CX for Windows

See Also

Step 1: Check System Requirements

The following Windows platforms are supported:

  • Windows 10 (Pro, Enterprise)
  • Windows 2012 and 2012 R2 (Foundation, Essentials, Standard, Datacenter)
  • Windows 2016 (Essentials, Standard, Datacenter)

A complete list of supported operating systems can be found here.

As a rule of thumb, your machine or VM needs at least one (1) CPU core and one (1) Gigabyte of RAM. Additional CPU time and RAM should be allocated based on:

  • Number of simultaneous calls the system handles.
  • Number of active users (100 users using the Web Client all day is very different from 100 IP Phones in hotel rooms making the occasional call).
  • Call recording use - places significant load on the system because of audio mixing and writing to storage.

Suggested hardware specifications for different usage scenarios can be found here.

Supported VM Platforms

The 3CX Phone System is well suited to be run as a Virtual Machine. Tested and supported hypervisor platforms are:

  • VMware ESX 5.X and above.
  • Microsoft HyperV 2008 R2 and above - see our Hyper-V Page for required settings.
  • KVM
  • Citrix XenServer 7.0 and above

Avoid using 3CX Phone System on converted VMs (P2V) because a converted virtual machine might have timing issues, which causes the guest operating system not to sync with the timer of the hypervisor.

Network, Firewall & Other Requirements

  • If you are installing on LAN, your network must be properly configured using a RFC 1918 private network (e.g. IP / range).
  • If the machine you are installing 3CX on is behind a NAT device, its ports need to be forwarded. See the Firewall & Router Configuration Guide to learn how to do this.
  • Use the latest version of Firefox, Google Chrome or Edge to access the 3CX web interface.
  • The machine you are installing 3CX on needs a constant internet connection to
    on port 443.
  • The machine also needs on demand HTTPs connection to*
    for 3CX Management Console downloads and other info.
  • To send emails via 3CX SMTP the machine needs to allow outbound TCP:2528.
  • See also Ports Used by 3CX Phone System for the list of required ports that need to always be available, i.e. not used by any other service.

Step 2: Prepare Your Host Machine for Installation

Tasks that MUST be completed before installing 3CX:

  1. Assign a static internal IP address to the host machine’s network adapter.
  2. Install all available Windows updates & Service packs.
  3. Any installed Antivirus Software should avoid scanning:
  • C:\Program Files\3CX PhoneSystem\*
  • C:\ProgramData\3CX\*
  1. If the host machine has multiple network adapters:
  • Disable unused network interfaces or Wi-Fi adapters.
  • Just ONE default gateway - DO NOT configure multiple adapters with default gateways!
  • Prioritize the primary network interface (the one with the default gateway configured) to the first position from: “Control Panel” > Network and Internet > Network Connections. Press the Alt key to reveal the File menu and click on Advanced” > “Advanced Settings.” The “Adapter and Bindings” tab > “Connections” section shows the available network interfaces. Ensure that the network card with the default gateway is at the top position.

Additionally, keep in mind the following for the machine you are installing 3CX on:

  1. Do not install VPN software or the TeamViewer VPN option.
  2. Ensure that all power saving options for your System and Network adapters are disabled. Set the system to High Performance from within “Control Panel” > “Hardware and Sound” > “Power Options”.
  3. Disable any installed Bluetooth adapter(s).
  4. The 3CX Phone System must not be installed on a host which is a DNS or DHCP server, or is installed to serve MS SharePoint, Exchange or any other SQL-based services.

Step 3: Install 3CX for Windows

  1. Download 3CX for Windows.
  2. Double-click on the setup file, read the system requirements and click Next.
  3. Read our configuration recommendations and click Next.
  4. Review and accept the license agreement.
  5. Select the installation folder path, 3CX Phone System needs a minimum of 10GB free hard disk space. You need to reserve additional space to store voicemail files, recordings & voice prompts. Choose the location to install and then click Next.
  6. Click Install to start the installation of the 3CX Phone System to copy all files and install the necessary Windows services. 
  7. After the 3CX installation is complete, you need to run the configuration wizard via a Web Browser or from the command line. Select option (1) to use a web browser on another machine, and point your browser to http://<ip of machine>:5015. Visit this guide for step by step instructions on running the first time configuration wizard.

See Also

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