"no dial tone" message

[tpegs]

when I try to connect to internet.
It's my dad's computer in the other room and this has happened three times before. Then, kinda dinkin around, I changed a couple settings, rebooted, and it was miraculously okay. This time I can't figure it out.
The modem shows enabled and working properly. It's plugged into the wall, the phones work and I can connect to the internet on my computer in the other room.
(xp pro sp2, 1g Athlon)

I run out of options on a fix, any ideas?
Thanks

-tpegs

 

[The General]

DSL = $14.95/mo

WHY ARE PEOPLE STILL USING DIALUP?!?

 

[TheMajor]

Check the cables. Use a phone to see if you have a signal/tone.

 

[Nitestick]

to the general: i don't think he will find that very helpful. insulting someone for there problem does not solve it. whatever his reason for having dialup its his reason

basically all you can do is check cables. is it an extension or a wall socket? if the modem is one to which you can connect a phone do so and the next time this message pops up check the handset to see if there really isn't a dialtone because it could be a hardware problem

 

[tpegs]

Sorry I took so long. Thanks for the replies.
Good point nitestick. Me having dialup at my current residence is not my decision so your comment general was rather ignorant.
But I ain't mad at ya.

After checking all the lines I found my dad has two splitters along his line and the line to his computer was unplugged. Yup, should've checked there first.
Thanks again fellas.

-tpegs