I have only power and ethernet lights on my 4100 B modem. Also, the ethernet light stays lit even when yellow cable is removed! Tech at ISP (AT&T) says the modem is defective. Shouldn't they replace it instead of me buying?

call the ISP,
if resetting it fails, call thE isp
when called a recording plays how to reset the SB4100
millions a day do.

Hi,
change your modem from PPPOE connection to Bridge mode make a dialup connection to connect internet.

authentication failed - call your (i believe u have cable isp ) to reset the line and modem . nothing wrong with modem

In all there should be lan led, dsl led, power led and internet led,
So if dsl and power led is glowing and others not?? than check the lan cable and even check the lan card of ur pc is it enabled or drivers are properly installed and same way try to check the modem configuration??

The modem advanced settings had VCI=35. It should be VCI=32 for QWest. See http://www.dslmodemsdirect.com/DSL%20Configuration/VPI_VCI%20configuration%20Page.htm for other providers.

It sounds like you've lost connect to your ISP. Have you checked with them to make sure you don't have an interruption of service?
If it's not an IOS, work with the ISP support technician to trouble shoot. They may have to replace the modem if they can't isolate the problem.

If the internet light is not on that indicates a prob with your ISP, call them up and arrange a service call. I had a similar prob a few weeks ago and they had to replace the drop to the house from the telephone pole.

*if the DSL light on your modem is blinking..
TRY: using different filters// check physical connection
IF: not resolved call ISP for a trouble ticket for their line department
*if all the lights constantly blinks
DO: purchase new modem, maybe deffective already or check if modem still under warranty so provider can replace it

NOTE: plug 4100 modem directly to the back of the computer tower without the linksys router and check if light status still the same...
HOW: cable connected from back of modem shud be plug in directly to port at the back of PC tower.. completly remove linksys and turn linksys off..

Unfortunately it sounds like the modem may need to be replaced. I had the same issue. Even after doing a complete shutdown, resetting all the cables, restarting the modem and then the computer, it still did not work. After you get the modem replaced, I would suggest you get a spare, possibably from e-bay, so if this happens again, you will not be without DSL Service.

hi,there are a lot of possibilities y ur dsl light wont stop flashing red, 1.could be hardware failure,2.defective lead light for dsl,3.or line issue on the network...i strongly recommend that you contact your isp or att provider so that test would be done by their tech support,...basically you have checkd all inside wirings n as you have said you even tested the nid already...have you tried changing the dsl cable or phone cable? have you tried using another modem? were you using a filter for your dsl? you have to consider also other emi/rfi or electronic interference....but most probably you might try upgrading your modem n see if your gonna get a steady dsl light...the ethernet plugs has no effect on the dsl light...its just the cable connection or line issue or defective modem...i hope this will help, pls feel free to ask if you need further astnce...