Diagnosing Modem Problems
Modems can be troublesome. If you have a telephone communications problem, there are a number of things you can do to check to see if the modem is working.
| Note | It bears repeating that the message often seen in the properties of any hardware device, “This device is working properly,” is often wrong. However, if you see “This device is not present, not working properly, or does not have all the drivers installed. See your hardware documentation,” you can bet that it is right. |
Here is a list of places in Windows where you can check to see whether a modem is working:
- Modem Properties in Device Manager, General page: If you see a message that indicates a problem, the modem might need to be reinstalled or replaced. Follow the directions or from the modem manufacturer to reinstall the driver.
- Query Modem: Go to Modem Properties from either Control Panel or Device Manager and click the Diagnostics tab if one is present. Then, click the Query Modem button and wait for the report. If the last couple entries in the report indicate OK, the query hasn’t detected a problem. You will often see the line “COMMAND NOT SUPPORTED” at one point in the report. You can ignore this.
- HyperTerminal: Go to Start > Programs (or All Programs) > Accessories > Communications > HyperTerminal, if it is installed. You will be prompted to set up a connection. Give it a simple name; you won’t be saving it. Figure 8.9 shows this page.
Figure 8.9: Naming a HyperTerminal connection.
Then, enter a single-digit telephone number. Make sure your modem is listed in the Connect using box. Click OK and you will be prompted to dial the number you entered. Click Cancel. You will see a blank HyperTerminal window. Type “AT” and then press . A working modem should respond with “OK,” as shown in Figure 8.10. Then, you can close HyperTerminal and elect not to save the connection.
Figure 8.10: Autodetecting the modem in HyperTerminal.
| Note | Some malfunctioning modems can nonetheless pass every one of these diagnostic tests. |
It is also a good idea to test a suspect modem with every function in which it can be used on the computer. This is to rule out the possibility that a program, rather than the modem, is malfunctioning. For example, if a modem works with faxing and Phone Dialer (Start > Programs (or All Programs) > Accessories > Communications > Phone Dialer), but not on the Internet, it is likely that the problem is in the Internet software or service rather than with the hardware.
| Note | You might find that Phone Dialer doesn’t work properly in Windows 2000 on certain machines no matter what you do. However, Windows 9x’s Phone Dialer (dialer.exe) might work in the newer Windows versions. If the modem will dial a number in Phone Dialer but do nothing else, the problem might very well be the hardware; we had a batch of new PCI modems that did this. The modems weren’t recognized by the Plug & Play system and had to be installed manually because they were defective. |
It is unfortunately common to get certain numbered error messages such as 619 või 693 when trying to connect using a modem. You might try several times in a row and get several different error messages. Often, these error messages bear no relationship to the truth. When you get one of these, first attempt to rule out the problem that the message indicates, assuming you can understand the message. The problem could be as simple as a bad telephone cord, the Caps Lock being on and altering the password, or that the telephone line is in use. Other possibilities include problems with the remote computer or service, or incorrect password or username. If the computer locks up every time you try to connect, you probably have a resource conflict. See Chapter 2 for information on resolving it.
| Note | Make sure that the user doesn’t plug a modem into a PBX telephone line. Even though PBX systems can use RJ-11/14 telephone connectors, the voltage and signal are different. This can damage the modem, but it might merely cause the computer to lock up. |
Once you have ruled these out, the next step is to reboot the computer, especially if you have a laptop. With some laptops, a design flaw causes certain functions not to work after the computer comes out of standby or hibernation. Rebooting might solve other problems as well. If none of these steps works, delete the connection and recreate it. If you still have the problem, it is time to try new hardware. Swap the modem for a known good unit and retry the connection. This is the perfect time to try an external modem if you have one. If you still can’t connect, and the modem is removable, try it in another system.
If a built-in modem on a laptop fails and you have reinstalled the driver to no avail, unless the laptop is under warranty, your only recourses are to install a PC-Card modem or use an external serial or USB modem. You might want to disable the built-in modem in the BIOS, if such a setting exists. Note, however, that sometimes seemingly permanent modem failures can occasionally resolve themselves over time.
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