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Finding correct driver for fax modem using VID & PID values

If you install a fax modem and Windows does not detect or install the modem drivers automatically, you’ll need to install the proper drivers provided from the manufacturer. This can be a problem if you do not have the driver files, and you don’t know the name or model of the fax modem.

If you are unsure what model of fax modem you have, you can check the device properties to determine what brand/model you are attempting to install.

This can be done by checking the VID and PID values of the device that is attempting to be installed.  The PID value provides you the Product ID and the VID provides the Vendor ID (the modem manufacturer, or chip-set manufacturer) such as Conexant/Rockwell, LSI/Agere, Motorola, etc.

In device manager, go to “Modems” and check if a modem name is listed here. If so, double-click the Modem name listed here and then click Details Tab. Select and Scroll down to “Hardware IDs” in property and here you’ll find the VID (Vendor ID) and PID (Product ID) (example is VID_0572&PID_1300)

If the modem is missing then the default Windows driver could not be installed and Windows will allocate the modem under an “Other Devices” or “Unknown Device” heading. If you double-click the Unknown Device or Other Devices and click Properties, Details tab and select “Hardware ID” from the property drop-down you should have the PID and VID or VEN and DEV values displayed here.  You can then search based on the found VID and PID values.

Searching Windows Catalog for drivers

Windows provides an extensive list of drivers, you can search here and download the compatible drivers that available on Window Update.

Type your search string, for example “PID_1329” will display all compatible drivers that contain the PID 1329 or enter “vid_0572” to display drivers that contain vendor ID 0572. The same PID could be used by other vendors, and the driver listed may not match the hardware you are looking for.

Searching for Vendor ID or Product ID

If you are unsure who the vendor, or product id you can search or for information on Vendor ID or Product ID.  Note that USB device information may not be available on these sites.

The original is no longer available.

Troubleshooting failed installation of a driver

You can check a log file to determine status, or cause of driver installation failure. This is especially useful for verifying why a driver cannot load.  This log can be used to check for any type of device including fax modems.  For Windows Vista and later operating systems, you can check the %systemroot%/inf/  file for information on the device installation. A driver may not install due to lack of a digital signature (digitally signed)

The importance of digitally signed drivers

Starting with new installations of Windows 10, version 1607, Windows will not load any new kernel mode drivers created by developers which are not signed by Microsoft’s Dev Portal. Why is this important? If you have an older device that is no longer supported, it won’t be digitally signed and may not install.  The following are the exceptions

Cross-signed drivers are still permitted if any of the following are true:

  • The PC was upgraded from an earlier release of Windows to Windows 10, version 1607.
  • Secure Boot is off in the BIOS.
  • Driver was signed with an end-entity certificate issued prior to July 29th 2015 that chains to a supported cross-signed certificate authority.
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