What Do I Do When My Modem Doesn't Work?

First, don't assume that the problem is with your modem.  Visit this page if you haven't, to make sure we're looking in the right place.  

If you still can't get online, the first question is -- is there really a problem with my modem? Fortunately, Windows provides a simple and highly reliable test:

• Click on Start / Settings / Control Panel / Modems / Diagnostics / [Select Modem] / More Info.  This should tell you if your modem is working OK...

If your diagnostics test presents you with a bunch of modem responses to the diagnostic queries, then your modem is working fine.  The problem lies elsewhere:  with your phone line, with the resource you are trying to dial into, or possibly with the program that is trying to use the modem.

If the program is a modern Windows modem, make sure it is using the right modem.  (You should delete any entries for modems that no longer exist to prevent this problem.)  

If the communications program is an older DOS-type of program, it may need special tweaking to work with your modem.  The main things to check are (a) that your software is looking for the modem on the right COM port number, and (b) that the software is not giving some long unnecessary string of commands that are designed to work with some other brand or modem of modem.  

• Not sure which COM port to use?  Repeat that diagnostic test, and notice which COM port (1, 2, 3 or 4) the modem is on.   Make sure the DOS software is using the same port.  Really old or badly-written DOS programs may not allow you to use the COM port you want.

Of course, if the modem fails the diagnostics, then you know that that's what we need to fix.  Don't start messing with your Internet settings, or the phone numbers you dial or the username/passwords you use to connect, if the problem is in the modem.  

Click here to continue working on your modem problem.

If you have an old computer with an external modem, you may want to replace it with an internal anyway, because (for technical reasons I won't go into here) your old computer may not be able to use the full speed of a fast external modem.

If you are switching from an external to an internal modem, (or vice versa), you will probably need to go into the CMOS settings -- your computer's power-on setup routine -- to deactivate (or activate) the serial connector at the back of the machine.   

Apart from that, replacing a modem is basically simple.  Just remove all reference to the old modem from Windows' Device Manager, then immediately shut down the computer and remove the old modem physically, before Windows tries to redetect and reinstall it.

Oh yes, when you buy a new modem, you may receive a CD or diskettes.  These may or may not actually be necessary for installation.  What is more important is to make sure that you have a copy of the installation files for Windows 95 or 98 (whichever is on your computer). This may be on a CD, or you might have them in a folder on your hard disk. C:\Windows\Options\Cabs is a likely location, but look also for a folder with a name something like "C:\WIN95" or "C:\W98".  (If you purchased a computer with Windows 95 or 98 installed and you didn't receive a copy of the installation files, demand one!)

Modern modems are supposed to be "plug and play":  You insert the modem card into your computer (or connect the modem via a cable), then turn on your computer, and Windows instantly detects the device, identifies it, and installs the software, politely asking you for a driver disk if it needs one.  When this works, it's wonderful.  When it doesn't, it can be a pain. 

Click here to work on your modem problem.

Borrow an ordinary home telephone and plug it into the wall jack where you currently have the modem plugged in.  Do you get a dial tone?  If you dial the number you are asking your modem to dial, what do you hear? You should hear the dialing, followed by the ringing, the answering, and the "squeal" of the modem at the other end trying to make a connection.  Watch your ears -- that squeal can be quite unpleasant.

Of course if you hear no dial tone, you know you have a problem that has nothing to do with your computer.  

If you hear a dial tone but the call doesn't connect, watch out for dialing prefixes:  maybe your computer is set to dial a "9" when you don't need one, or to dial "*70" when you don't have Call Waiting service on the line.  Seek out the "dialing properties" within your modem settings and make sure they are correct.

While you are there, make sure you are not dialing 1- and the area code on a local number.  

If the phone test works, remove the home telephone and plug back in the modem.  Now plug the phone into the other outlet on the back of the modem.  You should be able to get a dial tone again.  (If you don't, check your phone cables!  It's either them, or your modem is completely broken.)  

If all is still well, good.  You can leave the home phone plugged in there, so you can use the phone line for ordinary calls when your computer isn't using it.

(Note that the two outlets on the modem are labeled -- one is intended to connect to the wall, the other to a phone if desired.  You should follow those labels, of course, but the truth is most modems will work fine if you get it wrong.)

• Click on Start | Settings | Control Panel | System | Device Manager | select modem device | remove. 

While you are there, you can  also rip out any Com ports listed (unless they are supporting some other device, like a mouse). Don't worry, Windows will find them and put them back.  [Sometimes I skip this step the first time, to save time.  If I have to repeat the "remove and redetect" procedure, I include this step.]

• Restart your computer. Let Windows try to detect your Com ports and modem. Be patient.  Your computer might even ask to reboot after detecting a COM port.  Let it.
• If Windows doesn't detect your modem on boot-up, try the "Add Modem" Wizard (Start | Settings | Control Panel | Modems | Add ). 
• The "Add Hardware" wizard also works (Start | Settings | Control Panel | Add Hardware), especially if your need to redetect your COM ports.  
• Always let Windows try to detect your modem. If Add Modem Wizard does not detect your modem, do not waste time adding it manually. It won't work. 
• Don't be afraid to repeat the procedure a time or two until it works.  
• This procedure (removing a hardware component in Windows' Device Manager, then allowing Windows to detect and re-install it) is very useful in many circumstances.  The only time it is "dangerous" is if you are dealing with a used machine and may not have all the diskettes and CDs that came with it.  There is little risk with a modem, however, because Windows itself has drivers that work fine with most standard modems. 
• If you do use one of Windows default or generic modems to get online, and it works, great.  Once you are able to connect and are working online, you can go to the modem-maker's Web site and download and install the very latest driver file for your specific model, which might give you a bit more speed or add features.

Still no luck getting your modem working? Modems are rarely actually broken (except for those tiny PCMCIA modems that slide into laptop computers, which can sometimes overheat and die), so consider other possible explanations:

• If this is an external modem, check for loose connections, and verify that you have the correct power supply for the modem.  Also try replacing the cable that connects it to the computer with a newly-purchased "modem cable". Not every cable that fits these jacks is actually a modem cable.
• If this is an internal modem, open the case and briefly remove and "reseat" the modem in its slot.  
• If this is a very old computer, you might possibly have an "IRQ conflict". These were very annoying, which is one of the reasons people buy newer computers. Most frustrating of all, if you are trying to make such an old computer work, you probably won't want to hire the professional help it will probably take these days to get it working. 

By the way, if your modem is now working OK but you are not successfully connecting to the Internet, you might want to return here.