My brother just started having this problem a few days ago. He is losing internet connection frequently. When he connects directly to cable modem he has no issues But, when he connects with his router he starts losing connections. He has tried using new ethernet cables and even tried different routers and still has same problem. I have tried helping him ( try resetting routers, swapping cables, removing connections and rebooting, etc.) all to no avail. Any help would be greatly appreciated. Thank You.

Have you tried cycling power (unplugging and replugging) the cable modem, sometimes that gets the problem fixed, other wise try the same with the router. Does he even get an ip address when he connects via the router, or does he get no ip at all. (if it is an XP machine go to run and type cmd and hit enter, then type ipconfig /all and hit enter and see if he has an ip, if not, then you need to start tracing backwards from the computer). You may need to install drivers to use the router or wireless device (some times routers need drivers on the computer, however in most cases wireless transmitter/reciever units are either plug and play or need drivers).

Yes I have tried all that and it does get an ip but then it quits. There doesnt seem to be anything wrong with the routers.

I have tried different routers, changing cables, and also tried different ethernet cards and it still intermittently loses connection. The only way it stays connected is when it is directly hooked into cable modem and bypass routers. But, having tried 3 different routers I cannot believe that ALL 3 are bad. Anyone have any other suggestions. Any help would be greatly appreciated.

checked with the isp to see if the issue is on their end?

From everything that I can research on the internet this is a widespread problem with Comcast. They keep telling everyone that it is NOT on there end when everything points to the contrary. Several posts on different forums suggest the same problem my brother is going through. Someone told me to do and ipconfig and write everything down from my modem and then duplicate it in the router to cure the problem. I will try this and see if if works. Will post back if it does. Thanks again for all the help.

I had a similar problem once. I have a cable service with all 3 services: Phone, Internet, & Cable. The internet dropping out which was annoying. The problem got worse and the phones didn't work. Turns out it was the cable line. There was a very weak Signal which gets worse over time. The cable man repaired it at the source(on the pole). That could very well be you problem.

Knight