This is an excerpt from FAQ.txt, Provided with Windows 95 by Microsoft
Modems
[Q: Setup didn't detect my modem, how do I install it?]
To install a modem in Windows 95, go to Control Panel, and double click the Modem icon. Start the Modem installation wizard which will guide you through the installation of your modem.
NOTE: This procedure is for internal or external modems. PCMCIA modems automatically install when inserted (requires protected mode PCMCIA drivers).
[Q: My modem won't dial or connect. Why?]
NOTE: There is a troubleshooter for modem problems in Windows Help.
If your modem is not set up correctly, communications features may not function properly. The following procedures list steps to verify the correct operation of your modem and Windows 95 communications.
Because some communications programs designed for Windows 3.1 install incompatible driver files, which may cause COM ports and modems to stop working, first verify that the correct Windows 95 files are being loaded.
To verify that the required communications files are present:
1. Verify the files sizes and dates of COMM.DRV and SERIAL.VXD in the System directory against the original versions from the Windows 95 floppy disks or CD-ROM.
2. Confirm that the following lines are present in System.ini:
[boot]
Comm.drv=Comm.drv
[386enh]
device=*vcd
3. To revert to the default communications drivers for Windows 95, select communications port entries in Device Manager.
4. Run the Add New Hardware wizard in Control Panel to detect and install the Windows 95 drivers.
NOTE: Windows 95 does not load the SERIAL.VXD driver in System.ini. Rather, Windows 95 loads it on demand using the registry. Also, there is no corresponding file for the *vcd entry in System.ini. This is an internal file built into VMM32.VXD.
To verify the modem configuration
1. In Control Panel, double-click the Modems icon.
2. Verify that the manufacturer and model for your modem is correct. If not, run the Install New Modem wizard to detect the modem and confirm it with the current registry configuration.
3. If your current modem does not appear in the list of installed modems, click Add, and then select the appropriate modem.
4. If the manufacturer and model are not correct and are not available from the list, try the Hayes-compatible option for Generic Modem driver, set to the maximum baud rate supported by the modem, and then click OK. Remove any other modem entries in the list of eliminate conflicts.
To verify the modem is enabled
1. Double-click the System icon in Control Panel, and then click the Device Manager tab.
2. Select your modem from the list and click Properties.
3. Make sure the option, The Device Is Present, Please Use It, is checked.
To verify that the port is correct
1. Double-click the Modems icon in the Control Panel.
2. Select your modem, and then click Properties.
3. On the General tab, verify that the listed port is correct. If not, select the correct port, and then click OK.
To determine if a serial port I/O address and IRQ settings are properly defined
1. Double-click the System icon in the Control Panel.
2. Click the Device Manager tab, and then click Ports.
3. Select a specific port, and click the Properties button.
4. Click the Resources tab to display the current resource settings for that port. To find out the correct settings, consult the modem manual.
5. In the Resources dialog box, check the Conflicting Devices List to see if the modem is using resources in conflict with other devices.
6. If the modem is in conflict with other devices, click Change Settings, and then click a configuration that does not have resource conflicts.
Note: Do not try to use a modem on COM3 if there is a serial mouse or other device on COM1. Usually, COM1 and COM3 ports use the same IRQ and cannot be used simultaneously on most computers. The COM2 and COM4 ports have the same problem. If possible, change the COM3 and COM4 port to an IRQ setting that is not in conflict. Also, some display adapters have an address conflict with COM4 ports. To work around this conflict, use another COM port; or, replace your graphics adapters.
To check the port settings
1. Double-click the Modems icon in Control Panel, click a modem, and then click Properties.
2. Click the Connection tab to check the current port settings, such as baud rate, data bits, stop bits, and parity.
3. Click Advanced to check error control and flow control. If you are using Win 16-based programs, turn off these advanced features.
3. Verify the UART type.
Data transmission problems may occur when a baud rate greater than 9600 is selected on a slower 80386-based computer not equipped with a 16550 UART, or when performing other tasks during a file download. If problems or errors occur during transmission, try lowering the baud rate. Attempting to use baud rates greater than 9600 on computers equipped with 8250 or 16450 UARTs will probably result in dropped characters.
To check modem baud rate
1. Double-click the Modems icon in Control Panel.
2. Select the modem, and then click Properties.
3. Click the General tab, and then set the baud rate to the correct speed. Lower speeds may work, especially when using an older computer.
5. Click Only Connect At This Speed if it is not already selected.
NOTE: If the host system you are calling cannot communicate at the initial baud rate, it may or may not be able to negotiate a slower baud rate.
Tip: To optimize communications performance, you can set the baud rate higher if your computer has an 80486 or a Pentium(TM) processor.
To disable hardware flow control if your modem cable doesn't support it
1. Double-click the Modems icon in Control Panel.
2. Click a modem, and then click Properties.
3. Click the Connections tab, and then click Advanced.
4. Make sure the option Use Flow Control is unchecked.