A friend of mine recently had another friend install a new CD burner in his Compaq computer. The CD burner works o.k. (although the software for burning c.d.'s is a joke, but that’s another story.) Anyway. Ever since the C.D. burner has been installed, the modem doesn’t work.
The computer is a Compaq with Windows 98, P2, 64 megs of RAM. When he tries to dial up he gets an error message that says there isn’t a modem. It shows in the control panel as being there. Looking in the device manager, there are no conflicts to be found, and the modem is listed. It just won’t do anything. We tried re-loading the modem through the windows wizard for installing new hardware. Still no go.
One message we got while trying to make it work was that it may be “turned off”. I didn’t know they had a switch. 
Seriously though, I could find nothing that said on or off.
The only conclusion that I can come up with is that the modem is history and needs replaced. Incidently, at the same time, the mouse quit working and he replaced the mouse and now it works, which is another reason I think the modem is toast.
Any ideas? Thanks
There is not enuff information to make a call on whether the modem is toast.
When in doubt after installing new HW or SW and something goes astray, uninstall the new HW and/or SW and see if the problem rectifies itself.
Alternatively, connect the modem to another PC and see whether it fails there too. If so, it may be toast.
Well, the first think to try is a passthrough test. If there is a second phone jack on the back of the modem to allow a phone to passthrough the modem to the wall, plug a phone in there (if there is not one allready) and see if you hear a dial tone through the modem. No dial tone = dead modem
The next thing to try is to make the modem dial regardless if it hears a dial tone or not. In the modem properties from the control panel add an X3 to the modem command line. This may help the modem connect as well.
If that also does not work the remaining thing to try is completely uninstalling and reinstalling the modem. This is done by deleting every modem driver file off your computer, then removing all references to those modem driver files from the windows reg. Then you shut down the computer and physically remove the modem. Reboot the system w/o the modem in, and shut it back down. Then place the modem back in the computer, in a different PCI slot if possible, and reboot. Hopefully you’ll see an add new hardware wizard, and install the modem. (no wizard likely means the modem was not completely uninstalled properly. A bad modem will usually install, but then not work) Test the modem to see if it works. No work = dead modem.
Also, make sure the phone line going into the modem has a tone (and that it’s plugged in), all though the pass through test may answer this for you. You could also try yanking the burner out and seeing if that does anything.