Note: The very first thing before installing a modem is to ensure that any and all of the former modem information on a system is removed (uninstalled) both in Device Manager and Modems.
1. When a Plug and Play device is installed the first time, Windows automatically configures the device so it will work properly with other installed devices. As part of that configuration process, Windows assigns a unique set of system resources to all devices and these resources can include one or more of the following. FYI, this does not mean the actual modem driver.
Interrupt request (IRQ) line numbers
Direct memory access (DMA) channels
Input/output (I/O) port addresses
Memory address ranges
a. Each resource assigned must be unique or it will not function properly. For Plug and Play devices, Windows automatically ensures that these resources are configured properly.
b. Occasionally, two devices require the same resources, resulting in a device conflict. If this occurs, manually change the resource settings to be sure each setting is unique. However some resources, such as interrupts on PCI devices can be shared depending on the drivers and computer.
c. When installing a non-Plug and Play device, the resource settings for the device are not automatically configured. Depending on the type of device installed, you may have to manually configure these settings. Instructions for doing so should be supplied in the manual that came with it.
d. Generally, resource settings should not be done manually because when this is done, these settings become fixed and Windows will then have less flexibility when allocating resources to other devices. If too many resources become fixed, Windows may not be able to install new Plug and Play devices.
e. To manually configure devices, use the device Properties dialog in Device Manager.
Warning: Changing resource settings improperly can disable your hardware and cause your computer to malfunction or become inoperable. Resource settings should only be changed if you are certain the new settings do not conflict with other hardware, or if a hardware manufacturer has provided you with specific resource settings for a device.
2. To install modem hardware, it is recommended that you refer to the manufacturer's documentation. Generally, the following instructions apply:
a. For internal modems with jumpers, set the jumpers for Plug and Play or as instructed in the documentation.
b. Make sure that it is seated in the proper slot on the mother board.
c. If it is an external, make sure it is plugged into the power source and turned on before turning on the computer.
d. Connect either type modem to a usable phone line with the proper connector -- paying attention to whether there is a Line or Phone jack on the back of the modem.
3. The main decision -- when it comes to "modems" (Click to see an example of what we're talking about), is determining whether the problem lies in either a new installation, a change to the modem settings, installing or uninstalling devices or their drivers, whether the problem actually exists with the "Windows Dial-Up Networking" setup/software/settings, its contributed to the "Internet Service Provider (ISP)" access/phone connection, or something concerning a browser page display itself.
4. Remember: "We simply cannot tell you where a problem may exist unless you gave full details of the exact circumstance of how you decided there is a problem -- where you found or how you determine it, and reported the full accurate and complete errors for a modem/connection when one is displayed on the monitor/screen".
5. If the problem exist with an HFC (software modem), I simply do not get involved with their setup or reported problems. I'm sorry, and there is no need for reading further unless you desire to access some of the links furnished.
Note: However, some US Robotics Windows-only modems may not be detected properly by Win98/98 Second Edition. If a US Robotics Windows-only modem is not detected, and if the modem is not listed in Device Manager (either under the Modem or Other Devices branch), use the Wmregdel.exe file (tool) to clear all of the Windows-only modem-related registry entries, and then restart the system. The "Wmregdel.exe" file (276480 bytes) is located in the Drivers\Modem\3com-usr\Winmodem folder on the Win98/98 Second Edition CD-ROM or can be downloaded from the furnished link, which may be an updated copy.
6. Problems connecting or dialing out.
a. When you attempt a connection, the modem may not initialize and the dialing status may count down from only five seconds.
b. The "Modem Diagnostics" test (Start, Settings, Control Panel, Modem icon, Diagnostics, More Info) may report, "No modem found" and/or the mouse may hang.
c. Random or missing characters or incorrect line spacing may be displayed if you are connected to another workstation or a bulletin board service (BBS).
7. The modem may not dial the number.
a. It may dial the number, but not release the line. You may be able to hear the other person over the modem's speaker but won't be able to talk over the phone.
Note: If the mouse hangs when you run the modem test, note which COM port is being checked at the time, indicated in the status field. Be careful because an interrupt conflict can cause the system to stop when you are running the modem test.
Warning: When removing a modem (from the Modems section in the Control Panel), it is not automatically removed from any Dial-Up Networking (DUN) connectoids configured to use it. However, when reconfiguring Dial-Up Networking to select the correctly installed modem, the modem removed will no longer appear nor will DUN try to use it. Be advised, that until DUN has been reconfigured, this old modem entry will cause headaches.
b. Some things to check first:
(1) Make sure there are no other hardware devices using the same interrupt (IRQ) as the modem.
Note: By default, COM1 and COM3=IRQ4 and COM2 and COM4=IRQ3. Therefore each pair share interrupts (IRQs) by default and must be changed if COM3 or COM4 is used without creating conflict. However, if COM1 and COM2 are turned OFF in the CMOS/BIOS, COM3 and COM4 may use those interrupts as is. Also, if COM1/2 are turned ON in the CMOS/BIOS then the next available COM is #3, or greater for an internal device depending on the device settings, and you must ensure that a different interrupt (IRQ) is used. An external modem uses the comport to which it is connected and that port's IRQ only and that comport must be set to ON in the system CMOS/BIOS.
(2) Disable port B if you have an internal modem and no other serial device is attached. Enable port B if you have an external modem.
Note: Even if nothing is connected though an external connector as described above, ports will be in a reserved status (used) - simply because they are Turned ON, set by an option in a system BIOS. If there is/are no requirement(s) to use an external port adapter, set the option(s) for it/them to OFF in the system BIOS so these ports becomes available for some other internal serial device.
Caveat: If a serial device has a nonstandard base address - whether PnP or not, or should none of the above fore mentioned ports be available for assignment, Windows may automatically assigns a port "COM5", or higher when necessary. However, even though Windows does, the use of such a port or the device may be inoperable. Please read these two Microsoft Knowledge base articles:
8. "Intel DSVD Modem Not Detected by Windows 98 (Q191665)."
9. "Using Zoom Comstar Plug and Play Modems with Windows (Q146639)."
10. If there is another serial device, such as a mouse, trackball, digitizer tablet, scanner, fax card, net card, or sound card using the same interrupt, either change the interrupt of the modem, another device, or disconnect another device. Remove that device's interrupt assignment from Device Manager before trying to use it.
11. For information about how to change the interrupt of the modem or other device see the documentation for the device, or contact the manufacturer. The method used to change the interrupt depends on the device because it may be a jumper, a DIP switch setting, or software.
12. We all know the default COM1 is 3F8H-IRQ4 and COM2 is 2F8H-IRQ3. When attempting to use a third port, COM3 3E8H must be assigned an unused IRQ different than the default since it's interrupt mirrors COM1. This also applies when assigning a device to COM4 2E8H since it mirrors COM2. "IOW", each port must have its own individual and available IRQ which no other device has, [Q158114] and [Q123992].
Note: The configuration options explained in these articles make it easier to avoid hardware conflicts by changing port and interrupt setting. Basic Configurations provide the following:
a. A default configuration for each port which cannot be changed - default
b. Additional configurations for each port that allows editing of IRQ assignment, but do not allow change of I/O address
c. Additional configurations for each port by editing both the IRQ and the I/O range
13. Check the COMM.DRV= line in the [boot] section of the SYSTEM.INI file. If it indicates a third-party communications driver, comment out the line by placing a semicolon in front of it, and then add the following line to the [boot] section:
Note: Notebook/Laptop PCs that power down serial ports to save power must disable this feature. The power down serial port automatically turns off the power to the serial port.
14. "Create and Use the Modemlog.txt File (Q142730)".
15. "How to Enable the Cardfile Program in Windows 9x & ME (Q245157)" discusses problems due to an interrupt conflict on the same modem port by using the Autodial feature in Windows Cardfile (if installed), or using the Windows Terminal (if installed) to troubleshoot anomalies of this sort.
Note: If the conflict is on an interrupt other than the one to which the modem is set, Cardfile and Terminal may still work even though Dial-Up Networking does not.
(1) From the "Windows Accessory" group, open Cardfile.
(2) Enter a phone number in any card.
(3) From the "Card" menu, choose Autodial.
(5) Choose the "Setup" button, confirm that all settings are correct, and choose OK.
(6) Note: If there is a conflict on the same IRQ as the modem, the following message will be displayed:
Cannot dial modem: Check Control Panel to see that the modem is installed properly, and check the modem cables to see that they are connected properly
(1) From the "Accessory" group, open "Hyper Terminal" or simply type Hypertrm on the Start, Run line and press Enter.
(2) If it's never been used, a "Connection Description" window will be displayed prompting for a "Name". Simply enter "Test" at the section Name: and press Enter. Otherwise, click on File in the Toolbar and select New Connection.
(3) Complete the phone# for the ISP (7-digits) and press enter.
(4) Note: When the "Connect" applet comes up look at the phone# to be sure it's not repeated - on mine it is. I have to use the "Modify" button, clear the phone# entered, clear the check mark from "Use country code and area code" and click OK. I must then click "Modify", enter the phone# and press enter. Then I may press the "Dial" button to determine if the system and modem are properly configured.
(5) In the "Connect Using box, click "Direct To Com X" (where X is the port your modem is connected to) and then click OK. Click "OK" again.
(6) Upon return to the "HyperTerminal window, type atdt, a space, the seven ditit phone number for your ISP and then press Enter. You should hear the modem dial, see a connection made, and then disconnect, since this was only a test to determine system configuration with a comport and modem. Close everything without saving.
(7) If there is a conflict on the same IRQ as the modem, the following message may be displayed:
Terminal - Error
The selected COM port is either not supported or is being used by another device.
Select another port.
(8) Some problems, such as the modem not initializing and random characters being displayed on the screen can also be caused by incorrect communications settings. Make sure that all settings, including the Baud Rate, IRQ, and Base I/O Port address in the Device Manager | Ports are set correctly.
(9) Please read the Microsoft Knowledge Base articles at this "LINK" covering the subject of HyperTerminal.
Note: Clicking the link just provided opens the linked-site in a separate window for your convenience. Once the site opens, open any item of interest. Most browsers allow you to open a link in a separate window simply by right-clicking it and selecting, "Open in a new window". After you finish with the information displayed in that window, simply close it, and you'll pop right back to where you progressed from. Having to regenerate a main list sometimes can be time consuming - as you may well know.
16. Modem driver:
a. To start the System Registry Editor, click Start, Run, type regedit, and then press Enter.
Note: Click the Plus box in front of HKLM to expand it and continue clicking/expanding appropriate folders (each word preceded by a slash in the above key) until reaching the last folder named "Modem". Click it, to bold/highlight.
b. Upon reaching that folder, these will be subfolders listed there under with names containing four numeric numbers: zero, zero, zero, and zero, for the proper installation of a single modem and perhaps many others with the last digit represented by incrementing numeric digits. If there is only one listed - okay. However, should others be found, this denotes there have been several attempts of modem installation which went astray and were not properly installed/uninstalled. Which one should you leave depends on which one should be used? Look at each address and determine which contains the actual modem identification for the currently installed modem in the right window pane, listed in the key name INFPath. Write this name down since you'll be looking for that file later.
c. If that section contains more than a single subfolder labeled, 0000 (where nnnn is an incremental 4-digit number starting at 0000), more than one modem has been installed, was not uninstalled properly, or uninstalled period. Perhaps it would be to your advantage to delete the invalid and no longer used keys, however it want hurt to leave them alone. To delete an obsolete key, simply highlight (bold) the key in the left window pane, press the Del key on the keyboard keypad, and respond with an affirmative. You may further verify information contained in those key by opening the applicable modem INF file (the default \INF folder) with NotePad, and reading through it as you would any text document. If you ascertain that the key information no longer applies, it's your decision to delete it or leave it alone.
d. Start the FIND function by clicking Start, Find, Files or Folders:
(1) In the "Named:" section, type *.inf
(2) In the "Containing text:" section, type, or paste the name of the modem that was on the key "DriverDesc".
(3) Click the "Browse" button and progress to the %windir%\ INF folder, select it by clicking on it, and then click "OK".
(4) Click the "Find Now" button to search all INF files for that modem name. Make a note of which "INF" file(s) the modem name is listed in since you may want to open all of them in a text editor to see if there is a closer match for the particular modem you own, and is installed on the computer.
(5) When finished with the Registry Editor, click Registry in the main menu and select Exit. Or simply click the x in the URHC of the window to close the Registry Editor tool. Respond with an affirmative to save any editing.
(6) Progress to the "INF" subfolder in the Windows folder and find the file listed in that registry key. Open it in a text editor such as NotePad and search for the modem name installed. If it is not, you can pretty much be assured this is not the correct "INF" driver referenced for the installed modem, and if the information contained in the Registry was definitely erroneous, remove that key and reinstall the correct modem INF file, which may need to be downloaded from the manufacturer.
17. The "Interactive Modem Troubleshooter" site provides options for a user to select a problem by simply checking a box regarding a problem with a modem, a box for the type modem, and the speed at which the modem connects. You'll receive information explaining the possible causes of this anomaly.
18. "How to Connect to the Internet in Windows 95 and Windows 98 (Q138789)" explains the basic procedures for using Dial-Up Networking. In addition, read the information in the TechNet article, "Setting Up Dial-Up Networking for Calling an ISP."
19. "Cannot Create or Open a Dial-Up Networking Connection (Q254332)" explains problems which may be experienced when trying to setup a DUN connection.
20. "No Dial Tone When You Attempt to Connect to .... (Q142536)" gives some details for ascertaining a solid phone connection and setting the option, "Wait for dial tone before dialing".
21. "Troubleshooting Modem Problems in Windows 98 (Q190554)."
a. Since a standard modem is not dependent on the operating system used, there are additional troubleshooting steps which may be used to verify the functionality of a modem -- does it work at all.
Note: It may be difficult to differentiate between whether a standard modem or a Windows-only modem is being used. The best way to identify the type of modem is to check the documentation.
b. To check whether a modem is working correctly is by testing direct communication to the COM port.
c. To do so, type the following command at a command prompt (from within Windows 98, and at the MS-DOS mode prompt), and then press Enter:
echo ATM1L3X0DT12345 > COM(x) (where (x) is the serial port number to which the modem is connected/assigned) Note: The modem should dial the touch tone digits 12345
d. To hang up the modem afterwards, type:
echo ATH0 > COM(x) (where (x) is the serial port number to which the modem is connected/assigned)
Note: The ATM1L3X0DT12345 command is a signal to the modem to dial the numbers "12345". The first command, AT(tention) signals 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. L3 is a universal command to raise the modem's speaker volume to the maximum level. 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 DT command instructs the modem to dial the digits 12345.
e. The TechNet article "Chapter 21 - Modems and Communications Tools" covers just about every problem concerning a modem and connection within the operating system itself. If anything above has not cleared up the problem or you still have concerns, I suggest you click either link and do some reading.