Solved Can't connect to Xfinity Modem with Win8

I just switched to Xfinity and my Win 7 devices and Samsung phone are connecting to the modem just fine, but the Win 8 machine won't connect. The modem is a Technicolor TC8305C. Is this a common problem?
The Win8 machine is a dual boot and connects fine in Win7 so it definitely seems like a win8 problem.

P.S. I also have a Netgear Network Extender Model WN3000RP and it connects fine to that (in Win8).

P.S.S. This is all on Wi-Fi

Hey Jim, you have Comcast ? Look here Configure Windows 8 Network Settings for XFINITY Internet

Hi jds63, Thanks for the link. I followed the procedure, but, nothing improved. Talk to you tomorrow. I hafta go to bed now. Bye.

okrobie said:

Hi jds63, Thanks for the link. I followed the procedure, but, nothing improved. Talk to you tomorrow. I hafta go to bed now. Bye.

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YW, how are you connecting to Windows 8.1 PC ethernet (wired)? What did you use originally(router, modem) for this PC ? Comcast the internet provider ? May need to contact them.

You really do not have to do anything special. The problem is that Gateway has been recalled by Comcast, because of problems with it. Unless you have Digital Phone Service with Comcast. I would suggest just getting a decent Wireless Access point, and buy a Motorola/Arris 6412 modem. You can check on best rated Wireless Router/Gateways at smallnetbuilder.com.

I originally had the 6412 modem, a Cisco RV320, which I am still using, and a Engenius ECB350, with POE injector, for my main Access point to the router.

Hi jds63 and broe23, the problem is solved. I called Comcast (Xfinity) support and it was something silly on my part. I had to delete the modem from the list of network devices and then re-install it using the gateway password and it was online. I have found that you are correct broe23. The Technicolor TC8305C is a notorious POS, but I'm stuck with it due to budgetary issues, and for my purposes it is working well now.
Thanks guy's, Jim

okrobie said:

Hi jds63 and broe23, the problem is solved. I called Comcast (Xfinity) support and it was something silly on my part. I had to delete the modem from the list of network devices and then re-install it using the gateway password and it was online. I have found that you are correct broe23. The Technicolor TC8305C is a notorious POS, but I'm stuck with it due to budgetary issues, and for my purposes it is working well now.
Thanks guy's, Jim

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Glad you solved it ! Easiest solution call your provider as you pay for service regardless buying your own modem.

You can actually get a decent modem & Wireless Router pretty cheap. Especially if you look around on Newegg. I still have my 6412 and Wired Trendnet router waiting for someone that needs it. You would just need an Access Point, which would run you around $30. After I get tired of hanging on to old stuff, I just pass it along to someone looking for replacement equipment. Most just goes to my Brother, so he can have it for clients.

A little followup on this saga... I noticed some speed problems so I called Xfinity support. Naturally they needed the MAC address and serial number of my modem. When they put it into their computer it came up as a rented modem that was assigned to another party. They said no problem, just take it to the local Xfinity office and they would just re-assign it to me. Well when I got to the Xfinity office they checked it out and confiscated the modem. They said I could have it back if I would pay them $10.00 per month. I said if im going to pay $10.00 I wanted a better modem. I wasn't going to pay rent on the Technicolor POS. So they gave me a brand new SMC. I immediately called eBay and told them the story and they agreed to refund al of my money from the purchase of the Technicolor. So I was trying to avoid the rent on the modem and I wound up paying it after all. Oh well... it's one day at a time. Hope you get a laugh out of this. I sure did.

IPv6 is the major issue with speeds for Comcast. One you uncheck it in the network adapter, you should get back to real speeds.

Thanks broe23, I tried to uncheck the IPv6 in the SMC modem, which I am logged on to, but I couldn't find the place to do it.
I have been using the speed test recommended in the stickies of this forum and I am finding that my Win 7 machines are consistently faster than my Win 8 box. The speed on the Win 7 machines is ~29.5 mbps and the Win 8 is ~24.5 mbps. I'm not complaining because that is essentially a small difference. Do you have any idea about the possible cause of the difference?

EDIT: Interesting: The Win 8 machine is dual boot so I booted in Win 7 and the results of Speed Test were 21.8 mbps That gets Win 8 of the hook and makes the machine the suspect. I'll add more as I run further tests.

You need to disable IPv6 on the Network adapter on your computer. Comcast like others, are using a tunneling scheme.

I got to checking and found that the Wi-Fi adapter in this box is a cheesey POS and I couldn't figure out how to disable IPv6, so I ordered a D-Link Xtreme N DWA-552. That should do the trick.

I installed the new card and the download speed is on a par with the other machines in the household. Mystery solved. Thanks.