Modem Help Pages

Troubleshooting Modem problems in Windows 98.

The guide below gives some procedures to help you diagnose and fix problems when you are unable to dial out using your modem in Windows 98.

Verify Modem Type and Model

If your modem is detected by Windows 98, verify that the installed driver is the correct driver for your modem. To do so, click Start, point to Settings, click Control Panel, and then double-click Modems. Verify that the modem listed on the General tab is the correct modem.

If an incorrect or no modem is listed even though Windows 98 detected one, update the modem driver by following these steps:

1. Click Start, point to Settings, click Control Panel, and then double-click System.
2. Click the Device Manager tab.

*If it exists, double-click the Modem branch to expand it. If the Modem branch does not exist, look for an Other Devices branch, and then double-click the branch to expand it.

3. Double-click your modem, click the Driver tab, and then click Update Driver.

Windows 98 Update Device Driver wizard can search for the best driver or display a list from which you can select the appropriate driver. If you use the Update Device Driver wizard to search for a driver, you can also specify a location for the driver. Drivers for some additional modems are included in the Drivers\Modem folder on the Windows 98 CD-ROM. For a complete list of additional modem drivers included on the Windows 98 CD- ROM, please see the following article in the Microsoft Knowledge Base:

If the correct driver appears in Device Manager but your modem still does not work properly, troubleshoot the problem using the appropriate methods below for your modem type.

Modem Type

The method you use to troubleshoot your modem problem depends on the type of modem installed in your computer. There are two general types of modems:

Standard modems
Windows-only modems
Standard modems can be internal or external, Plug and Play, or not Plug and Play. Windows-only modems are internal Plug and Play modems, and are dependent on drivers in the Windows operating system to function properly. Standard modems operate independently of the operating system being used.

Physically, it can be difficult to differentiate between a standard modem and a Windows-only modem. The best way to identify your type of modem is to check the documentation included with your modem or computer (if the modem was preinstalled).

Windows-only Modem Troubleshooting

Because a Windows-only modem depends on drivers specific to the operating system to function, the modem must be recognized by the operating system before any troubleshooting can be done. This also precludes any troubleshooting outside of the operating system, or, in the case of Windows 98, at a command prompt in MS-DOS mode.

Windows 98 should normally detect the presence of a Windows-only modem and add it in Device Manager. If a Windows-only modem is not detected, there can be one of three causes:

The Windows-only modem has previously been detected (whether drivers were installed for it or not).
In this case, the Windows-only modem should be listed in Device Manager, and the driver can be updated using the procedure described above in the "Verify Modem Type and Model" section.
The Windows-only modem drivers were installed and then removed, but some registry entries remain.
The registry entries need to be removed before the Windows-only modem can be detected again. For 3Com US Robotics modems, use the Wmregdel.exe tool included on the Windows 98 CD-ROM to clear all Windows-only modem-related registry entries, and then restart your computer. The Wmregdel.exe tool is located in the Drivers\Modem\3com- usr\Windows-only modem folder on the Windows 98 CD-ROM.
If Windows 98 still does not detect your Windows-only modem, the Wmregdel.exe tool may not have removed all the necessary registry entries. To resolve this issue, contact 3Com US Robotics to inquire about the availability of a fix for this issue.
Something is physically wrong with the Windows-only modem.
Contact your modem manufacturer for the correct procedure to test your Windows-only modem.
If there are no default drivers in Windows 98 for your Windows-only modem, Windows 98 prompts you to search for drivers. Drivers for your Windows- only modem may exist in the Drivers\Modem folder on the Windows 98 CD-ROM.

If no drivers are located for your Windows-only modem, Windows 98 adds it under the Other Devices branch in Device Manager. You can use Device Manager to update the existing drivers with drivers provided by your Windmodem's manufacturer. Note that Microsoft Windows 95 drivers often work fine in Windows 98.

If your Windows-only modem still does not work after installing the drivers, there may be a resource conflict or an issue specific to your Windows-only modem. To determine if this is the case, see the appropriate section below.

For more information about Windows-only modems and how to troubleshoot them obtain the US Robotics Windows-only modem FAQ from the following 3Com U.S. Robotics Web site:

http://www.usr.com/home/online/trblshot/13011.htm

Standard Modem Troubleshooting

Because a standard modem is not dependent on the operating system being used, there are additional troubleshooting steps that can be used to verify the functionality of the modem.

Check that the modem is working correctly by testing direct communication to the COM port. To do so, type the following command at a command prompt from within Windows 98 and in MS-DOS mode, and then press ENTER

echo ATM1L3X0DT12345 > COM<x>

where <x> is the serial port number to which the modem is connected.

The modem should dial the touch tone digits "12345."

To hang up the modem, type

echo ATH0 > COM<x>

where <x> is the serial port number to which the modem is connected.

The ATM1L3X0DT12345 command is a signal to the modem to dial the numbers "12345." The first command, Attention, signals to the modem that it is about to receive information. M1 is a universal command to turn the modem's speaker on if it is off by default. L3 is a universal command to raise the modem's speaker volume to the maximum level if it is at the lowest by default. X0 is a universal command that signals the modem to run the command without waiting for a dial tone (useful if modem and voice calls use the same phone line), and the DT12345 command instructs the modem to dial the digits 12345.

NOTE: To restart your computer in MS-DOS mode, click Start, click Shut Down, click Restart In MS-DOS Mode, and then click OK. To quit MS-DOS mode, type "exit" (without quotation marks) at the command prompt, and then press ENTER.

In both cases, the modem should respond with a dial tone or communication signal.

If the modem does not respond with a dial tone or communication signal in MS-DOS mode, there may be something physically wrong with either the modem or the COM port. To determine if this is the case, contact your modem or computer manufacturer to verify the functionality of your hardware.

If the modem does not respond with a dial tone or communication signal in Windows 98 but does respond in MS-DOS mode, Windows 98 may not be communicating correctly with your COM port. This behavior can occur for either of the following reasons:

The COM port has not been detected.
Click Start, point to Settings, click Control Panel, double-click Add New Hardware, and then follow the instructions on your screen to detect the COM port.
The serial port device drivers are corrupt.
Use the System File Checker (SFC) tool to verify the integrity of the Serial.vxd, Vcomm.vxd, and Serialui.dll serial port drivers.
Resource Conflicts
If your modem is set to use the same resources as another device in your computer, there is resource conflict, and either or both of the devices may not work. Resource settings a standard modem uses include an input/output (I/O) address and interrupt request (IRQ). In addition to these, Windows-only modems also frequently use a direct memory access (DMA) setting.

Use Device Manager to determine if there is a resource conflict. To do so, follow these steps:

1. Click Start, point to Settings, and then click Control Panel.
2. Double-click System, and then click the Device Manager tab.

*Normally, if there is a resource conflict that prevents one device from working, an exclamation point in a yellow circle is displayed for the device. In some cases however, a Windows-only modem that conflicts with another device may not have an exclamation point in a yellow circle. In this case, you must determine if there is a conflict yourself.

To view the resource settings used by your modem, follow these steps:

1. On the Device Manager tab, double-click the Modem branch to expand it.
2. Double-click your modem, and then click the Resources tab.

*NOTE: If the Resources tab does not exist, your modem's resources cannot be configured by Windows 98. To determine the resources your modem is using, consult the documentation included with your modem.

3. Note the resource settings used by your modem, and then click OK.
4. Double-click Computer to view all the resource settings in use on your computer, listed by resource. Click each resource setting to determine if there is another device using any of the same settings your modem is using.

*NOTE: Hardware using the IRQ Holder For PCI Steering setting can be disregarded. This does not cause a resource conflict.

If there is another device using any of the same settings as your modem, you need to change the setting for that device or your modem. If the device is a Plug and Play device, you may be able to do this on the Resources tab in Device Manager, although some devices may require you to change jumper pins or dip switches on the device itself. To determine the best way to change resource settings for the device, consult the documentation included with the device or your computer.

Because Windows-only modems are Plug and Play, you should be able to change the settings for the modem using Device Manager. To do so, follow these steps:

1. Double-click the Modem branch to expand it, and then double-click your Windows-only modem.
2. On the Resources tab, click the Use Automatic Settings check box to clear it.
3. In the Setting Based On box, click a basic configuration with settings that do not conflict with any other device.

*NOTE: If none of the available basic configurations have settings that do not conflict with any other device, you may need to change some resource settings manually. To do so, click the last available basic configuration, and then double-click the resource setting you need to change.

Specific Issues

Sound4 Windows-only modems:

The Sound4 Windows-only modem may not be detected properly during the Windows 98 upgrade process. If your Sound4 Windows-only modem is not functioning properly after you upgrade to Windows 98, view Packard Bell's Web site for troubleshooting information, or contact Packard Bell Technical Support.

US Robotics Windows-only modems:

Some US Robotics Windows-only modems may not be detected properly by Windows 98. This may occur even if the modem was working properly in Windows 95. If your US Robotics Windows-only modem is not detected when Windows 98 starts and is not listed in Device Manager (either under the Modem or Other Devices branch), use the Wmregdel.exe tool included on the Windows 98 CD-ROM to clear all Windows-only modem related registry entries, then restart your computer. The Wmregdel.exe tool is located in the Drivers\Modem\3com-usr\Windows-only modem folder on the Windows 98 CD-ROM.

If Windows 98 still does not detect your US Robotics Windows-only modem, the Wmregdel.exe tool may not have removed all the necessary registry entries. To resolve this issue, obtain the updated version of the Wmregdel.exe tool from the 3Com US Robotics site.

http://www.usr.com/support