Toshiba V.90 - Manual (Page 21)

Setup
Function check
2
NOTE: HWSETUP in Windows does not enable changes to
ports.
Function check
Use the Diagnostic function accessible in the Modems Properties
window to check the functions of your internal modem.
To run the diagnostics:
1 Click the Diagnostics tab in the Modems Properties window.
Modem Properties window
2 Select the COM Port for Toshiba Internal V.90 Modem.
(This is the COM port for the Toshiba internal modem.)