Ok we have 4 bedrooms. I had the modem in one bedroom then transferred it to another one today. After hooking up the modem it will not connect to the Internet. If I put it in the other too
 It still works. What is up?  The light for power comes on & only the receiving light blinks.

Also the house was only built 3 years ago so everything is new. I don't think the line is split. When I get chance I will check in the basement

Lol yeah me too. I called I believe when they hooked it up the first time they only did the one outlet. Should be done Tuesday

That was going to be my next question: can you get a cable signal on a tv on that connection.

Sounds like a splitter issue, then. For the hell of it, hook up a tv and let it do a standard CATV channel search. You might get nothing, you might get a small mess of channels.

That's what I say, but when I don't pay my comcast bill for a while and they cut me off, I leech from 1 of the 2 unsecured signals around here until my account is happy again. It gets the job done.

I believe the typical guidance is for the lines on a modem to be a home run to the tap. If it's split, it could throw the signal levels out of the acceptable range. In Five Aces pic above, the numbers by the outputs on the three way splitter indicate how many dB is lost coming out of that line. I'm not a cable tech, so I don't know what the range is, but I do know that if you're outside of it, internet won't lock, you could have picture loss on the TV (in an analog world, it would come across as snow or interference, digital signal loss means the picture is cut out entirely), or you'd have no dial tone for CDV service.

It happens, but your tech should be able to fix you up. Let me know how you made out in the end.

Bah, just run some cat5 to where you want the connection. Or use real cats, I don't care.