At the time of installation, Fax Voip T.38 Modem always trying to automatically configure the Windows Fax Service to use Fax Voip 14.4K TAPI Voice-Fax Modem devices to send and receive faxes.
To manually configure Windows Fax Service in Windows 11, Windows 10, Windows 8/8.1 or Windows 7, see To configure the Fax Service in Windows 11.
To manually configure Windows Fax Service in Windows Server 2022, Windows Server 2019, Windows Server 2016, Windows Server 2012/2012R2 or Windows Server 2008R2, see To configure the Fax Service in Windows Server 2022.