Hello - Please bear with me. I'm not very networking literate.
We are switching from Verizon DSL to Comcast. The ethernet cable goes from modem into a router and then to three different Windows 7 PCs.
I hook up the Comcast cable modem (no ethernet cable). All the lights but 'Link' come on. I swap the ethernet cable from the Verizon modem to the Comcast modem. Now the 'Link' light comes on orange, blinking furiously, and all three PCs get the famous "Connection has failed with error 651" message.
I remove the router and run the ethernet cable directly from the Comcast modem to a PC. The 'Link' light turns to green and the PC connects fine.
I replace the first router with another router and get the same "error 651" message again.
I try a new ethernet cable from modem to router and still get the "error 651" message.
The first router is a two year old Netgear and the second router is a five year old Buffalo. The Netgear works fine with Verizon DSL. The Buffalo worked fine with my Comcast cable modem at my old address a couple of days ago. (I did connect to Verizon DSL through the Netgear for the past couple of days and I am doing so now).
I went back to the Verizon DSL modem and all three PCs connect fine.
I have rebooted PCs, powered modems off and on. I was able to get intermittent connections through the router on two PCs yesterday while fiddling around, but today just the "error 651" message.
What do I need to do to get my Comcast internet connection working through the router?
This is NOT the proper sequence to connect things. Do this:
1. Assuming the routers you have are not specific DSL models, disconnect them from computers and modems and reset the one you intend to use with Comcast to factory defaults, consult your manual for the exact method of doing this. THIS IS CRITICAL! Most DSL connections use PPPoE instead of an automatic DHCP connection like Comcast does, so unless you reset your router(s), they are improperly configured and will NOT connect to your Comcast service.
2. Once the router is reset (whichever you intend to use, I would pick the newest and fastest model personally ;-), go and reset the Comcast cable modem. You don't say what it is so I can't give exact instructions. If a regular cable modem, simply remove the power cable for 10 seconds or so and plug it back in. If it's an EMTA (cable modem with phone jacks), then press and hold the reset button until the EMTA reboots.
3. Now connect the router's WAN/Internet port to the cable modem's ethernet port using a good cat5e ethernet cable.
4. The router should now start talking to the cable modem.
5. Connect each of your computer's to the LAN ports on the router.
And you're done. If any of this doesn't work, then describe exactly what each device is, how they are connection, which step failed, what the exact LED lights say, etc.
Thanks for your reply. Life got in the way today so I won't get to your list until tomorrow (or the next day).
Before I tackle that, though, Merge or Delete Network Locations shows four networks on the primary PC: 0016017F9FBE, Network, Network 2, and Network 3. Currently I'm using Network 2 on Verizon DSL. The rest all are 'Not in use' and all four are 'Unmanaged'. I haven't checked the other two PCs but they must have at least one Network for Verizon DSL.
Should I delete any or all of these networks before I tackle your list?
I would delete ALL but the one you're working on (you can't delete the active network). Then same dialog that has "Merge or delete network locations" just change the name of the network to "Home" and press OK. Underneath the "Home" network name in Network and Sharing Center, there should do a link that says "Home network". If it doesn't say that, click on it and select Home network and press the Close button.
When you get to re-connecting to the reset router, you MIGHT have a new network name here. If so, simply do the merge/delete thing again, delete the unused one and then rename the network to "Home" or whatever. The name is unimportant, but make sure the type is "Home network".
It took a while to get to all three computers, but your directions worked. I think deleting the extra, unused networks did the trick. Now all three computers see the internet fine. Thanks for your help.
This happened to me. I could get onto to facebook but not onto comcast home page. It turned out that my drivers were bad. The sad part is, that when I was on line I kept getting a message that I had a problem with my drivers yet I was ignoring it. My friend was helping me trouble shot and he said your drivers are bad. Took him all of five minutes to fix it. Comcast told me I had a bad network interface card. But I was using a wireless laptop.