Log and View Modem Commands

Applies To: Windows Server 2008

You can use this procedure to configure Windows to record all modem commands and responses to a log file.

The ability to view the commands sent by your computer to the modem and its response can be very helpful in troubleshooting problems connecting to other computers.

Membership in the local Administrators group, or equivalent, is the minimum required to complete this procedure.

To log and view modem commands

  1. In Control Panel, click Hardware and Sound, and then click Phone and Modem Options.

  2. On the Modems tab, click the modem whose commands you want to log, and then click Properties.

  3. Click the Change Settings button, if the button is present on the General tab. If the User Account Control dialog box appears, confirm that the action it displays is what you want, and then click Continue.

    If the Change settings button is not present, the modem does not support the ability to change modem settings. Refer to the documentation provided by your modem vendor.

  4. Click the Diagnostics tab.

  5. In Logging, select the Append to Log check box if you are working on a computer running Windows Vista or the Record a Log check box if you are working on a computer running Windows Server 2008.

Additional considerations

  • Click View Log to display the log file, which identifies the modem and displays information about how it is functioning.

  • Commands sent to the modem are captured in the file:


    Model is the name of the modem as it appears in the list of installed modems on the Modems tab of Phone and Modem Options.

  • In Windows Vista, logging is always turned on, and the log is overwritten at the beginning of every session unless you select the Append to Log check box. In Windows Server 2008, logging is turned off unless you select the Record a Log check box.