# How to debug a modem problem? **URL:** \ **Category:** Factual Questions\ **Created:** [December 8, 2006, 4:43pm UTC](https://boards.straightdope.com/t/how-to-debug-a-modem-problem/383354 "2006-12-08T16:43:34Z")\ **Posts on this page:** 5\ **Page:** 1
**Author:** ![Fir\_na\_tine](https://avatars.discourse-cdn.com/v4/letter/f/a587f6/32.png) [@Fir\_na\_tine](https://boards.straightdope.com/u/Fir_na_tine)\ **Post date:** [December 8, 2006, 4:43pm UTC](https://boards.straightdope.com/t/how-to-debug-a-modem-problem/383354/1 "2006-12-08T16:43:34Z")
My home machine is a 3 to 4 year old Dell running Windows XP. At home, I’m stuck with a dial up modem connection. It works OK for email and so forth. For about the last 30 days, the modem fails to detect the dial tone about 50% of the time. Do a reboot and it works fine. Couple of days ago, when I hit Connect, the machine reboots itself! Does it each and every time. Brought the machine into our local Best Buy for service figuring the modem had crapped out. They plugged it in (the entire CPU) and say it works fine, dials out OK right now. I’ll pick it up later today and bring it home. The phone line I’m using seems to be OK, I tested it with a phone and the dial tone is fine. What tests can I run at home to work my way through this problem and figure out what’s wrong? 😕 Jim ---
**Author:** ![ultrafilter](https://avatars.discourse-cdn.com/v4/letter/u/3d9bf3/32.png) [@ultrafilter](https://boards.straightdope.com/u/ultrafilter)\ **Post date:** [December 8, 2006, 5:47pm UTC](https://boards.straightdope.com/t/how-to-debug-a-modem-problem/383354/2 "2006-12-08T17:47:45Z")
It’s probably not the modem itself, but some piece of software you have installed. At the very least, you should check for an updated driver. ---
**Author:** ![Fir\_na\_tine](https://avatars.discourse-cdn.com/v4/letter/f/a587f6/32.png) [@Fir\_na\_tine](https://boards.straightdope.com/u/Fir_na_tine)\ **Post date:** [December 8, 2006, 6:28pm UTC](https://boards.straightdope.com/t/how-to-debug-a-modem-problem/383354/3 "2006-12-08T18:28:41Z")
[QUOTE=ultrafilter] It’s probably not the modem itself, but some piece of software you have installed. At the very least, you should check for an updated driver. [/QUOTE] Assuming I can make an internet connection, how do I search for a driver? ---
**Author:** ![ultrafilter](https://avatars.discourse-cdn.com/v4/letter/u/3d9bf3/32.png) [@ultrafilter](https://boards.straightdope.com/u/ultrafilter)\ **Post date:** [December 8, 2006, 6:43pm UTC](https://boards.straightdope.com/t/how-to-debug-a-modem-problem/383354/4 "2006-12-08T18:43:21Z")
Your best bet is to go to [Windows Update](http://windowsupdate.microsoft.com) and see if it has an update. ---
**Author:** ![Derleth](https://avatars.discourse-cdn.com/v4/letter/d/b9e5f3/32.png) [@Derleth](https://boards.straightdope.com/u/Derleth)\ **Post date:** [December 8, 2006, 7:14pm UTC](https://boards.straightdope.com/t/how-to-debug-a-modem-problem/383354/5 "2006-12-08T19:14:49Z")
Is it an external modem or internal? If it’s internal, give it to someone you don’t like and get an external one. If it’s external, someone might be able to help you. [A quote on the matter](http://linuxmafia.com/~rick/faq/): > [@](#): > > A large part of diagnosis is breaking down large problems into series of smaller ones, and solving them systematically. Consider an external modem that won’t dial: You’ve tried typing “AT” (modem, come to attention) in a modem app such as minicom for Linux, but the modem isn’t replying “OK”, as it should. That command goes first to the selected serial port. (You’ve verified that minicom’s using the correct port.) So, you think, OK, is the port bad? You test this by connecting a serial mouse to the port, and seeing if mouse software (such as gpm) works. If the mouse software fails, then the port is non-functional, or is disabled in hardware, or has no driver in the OS. Fix the hardware and/or furnish the driver. > > [snip] > > By contrast, if an internal modem doesn’t work fully from the start, most means of diagnosis are unavailable thereafter: The serial port and modem on the card are hard-wired to one another, and so cannot be tested separately. The lack of activity lights (LEDs) means that, even if you’ve done everything right except enable modem-command echo, you’ll never notice the resulting modem-traffic activity telling you you’re 98% done — because there are no lights to tell you so. Internal modems don’t even make a good espresso.