> For the complete documentation index, see [llms.txt](https://prosbcdocs.telcobridges.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://prosbcdocs.telcobridges.com/configuration-details/configuration-by-use-case/3cx-phone-provisioning-configuration/configuration-for-3cx-pbx-server-with-the-prosbc-to-receive-t38-faxes.md).

# Configuration for 3CX PBX Server with the ProSBC to receive T38 Faxes

### Introduction

This document provides instructions on how to configure 3CX PBX Server with the ProSBC to receive T38 Faxes. Please visit the following link for more details about [Configuring Fax Server in 3CX PBX Server](https://www.3cx.com/docs/manual/fax-server/)

### 3CX PBX Fax Server Configuration

3CX Phone System includes a pre-configured fax extension (ext: 8888). This extension is used by the 3CX Fax Server for incoming fax calls, which will then be routed to an email address.

<figure><img src="https://docs.telcobridges.com/w/images/thumb/c/c3/3CX_FAX.png/500px-3CX_FAX.png" alt=""><figcaption></figcaption></figure>

* In the 3CX Management Console, go to Settings > FAX Server.
* Enter an email address to forward the faxes received on this number.
* Select the fax extension that should receive incoming faxes. You can use the default built-in ‘8888’ extension.
* Assign one or more available DIDs to the fax server.
* Click OK to save.

### ProSBC T38 Configuration

To enable T.38:

1\. Select Profiles from the navigation menu.

<figure><img src="https://docs.telcobridges.com/w/images/8/8e/ConfigureFaxPassthrough_0.png" alt=""><figcaption></figcaption></figure>

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2\. Click Create New Profile

<figure><img src="https://docs.telcobridges.com/w/images/3/37/ConfigureFaxPassthrough_1.png" alt=""><figcaption></figcaption></figure>

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3\. Enter a name for the Fax Profile.

* Click Fax/Modem Relay to expand the view.

<figure><img src="https://docs.telcobridges.com/w/images/e/e3/ConfigureFaxT38_0_A.png" alt=""><figcaption></figcaption></figure>

4\. Configure the settings:

* Set Enable Fax/Modem Relay to enabled.
* Set Detection Mode to Standard.
* Set Relay Mode to T.38.

<figure><img src="https://docs.telcobridges.com/w/images/0/09/ConfigureProSBCFaxT38_0_A.png" alt=""><figcaption></figcaption></figure>

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5\. Verify that the Profile was successfully created message is displayed.

<figure><img src="https://docs.telcobridges.com/w/images/f/f3/ConfigureFaxT38_2.png" alt=""><figcaption></figcaption></figure>


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