modem not working

a friend of mine has a computer with windows xp profeesional operating system and is trying to get on the internet through his phone line but the error says modem failure when i look the modem has a yellow eplanation mark what could be wrong and how can we fix this so he can get on the internet. i am using a public computer to ask for help

 

In the device manager where the yellow ! is displayed, double click on it and it should give you a little more information as to why the modem doesn't work. It could be an resource/IRQ conflict, or it could be a missing driver for the modem itself, which should be included on an installation CD if it came with one.

 

everything was on my friends computer when he got it i don't understand how i can fix the problem if i don't know what i am looking at. and where to get the drivers i know nothing about computers can you tell me what i should be looking for

 

the modem shows a yellow circle i am trying to use a free internet but the modem does not work what does the yellow mark with a black mark in the middle mean and how can i fix it it says motorola

 

i was told by another person at another forum to uninstall the modem through add remove programs now the computer does not detect the modem how can i find the right on for the computer without opening the case it asks me to pick one from a list can you help me tmm5899