I CANNOT CONNECT TO LIVE SINCE DECEMBER UPDATE. MTU ERROR, PLEASE HELP!!!!!

I HAVE NOT BEEN ABLE TO CONNECT TO XBOX LIVE SINCE THE DECEMBER UPDATE.  I RAN THE UPDATE FROM A FLASH DRIVE AND IT TOOK BECAUSE MY BACKGROUND HAS CHANGED.  I HAVE A TOP OF THE LINE NETGEAR ROUTER WITH MTU'S SET AT 1500 AND A TOP OF THE LINE MODEM FROM COMCAST.  MY CONNECTION SPEED IS ALMOST 40 MBPS.  I HAVE RUN ALL THE TROUBLESHOOTING STEPS MULTIPLE TIMES AND CALLED INTO SUPPORT.  I AM GETTING VERY FRUSTRATED.  ANY HELP WOULD BE APPRECIATED. I HAVE ATTACHED THE NECESSARY INFO BELOW WITH THE CODES.

What Country/State/Province do you live in? UNITED STATES
Modem brand & model number: SMC Networks: SMCD3GNV

Router brand & model number: NETGEAR N900: WNDR4500-100NAS
If Wireless, are you using a white or black external adapter, or an internal (Xbox 360S) adapter? BLACK EXTERNAL ADAPTER W/2 ATTENAES
Things you have tried: ALL THE STEPS LISTED ON THE XBOX LIVE SUPPORT SITE MULTIPLE TIMES AND CALLED INTO SUPPORT AND FOLLOWED THOSE. I HARD WIRED STRAIGHT TO THE MODEM AND STILL GET MTU ERROR.

Is UPnP Enabled? Yes/no/Unknown YES
Do you have a NAT error? If so, what is your NAT? NO
Any Error Codes you encounter: GETTING THE MTU ERROR.  EVERYTHING WORKED UNTIL THIS LAST UPDATE IN DECEMBER. ROUTER IS SET TO 1500.
Who is your ISP(Internet Service Provider)? COMCAST XFINITY
After you run "Test Xbox LIVE connection" press “Y” for "More Info”. In the pop-up that appears, what are the following values, if shown? (If a value below does not appear for you, just leave it blank.)
W: 0000-0021
X: 0000-F001
Y: 0000-0000
Z: 0000-0000
ID: FFFF-FFFF

 

Question Info


Last updated July 4, 2018 Views 2 Applies to:

Just because your router is set to 1500 for the MTU doesn't mean that you still can't have an MTU issue.  MTU (see en.wikipedia.org/.../MTU_(networking) for more info about MTU) Errors can be caused by not having enough bandwidth on the network as well or even your ISP's MTU settings.  For troubleshooting check out: support.xbox.com/.../error-your-network-does-not-have-sufficient-mtu-setting-979104 .. if those step do not work then you will want to call 1-800-469-9269 option 2 for the connectivity department.  The DB Update in December only made light of an issue that you were already having.  The new DB is better attuned to be able to detect problems where the older DB's weren't able to detect them.  So you were still having MTU issues you just didn't know about it because the older DB's weren't able to detect it.

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Hi Chingon,

Quick question - How far away is your router? Also, are you using anything like a Turtle Beach Wireless Headset?

Thanks!

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The router is about 12-15 feet away with a straight line shot to the XBox and I am just using a regular XBox headset.  Thanks.

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The MTU error could be caused from Wireless interference. Try changing the wireless channel to 1 or 11. You can do this by logging into your router.

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Get your modem reprovisioned. This requires you call Comcast and actually have them reregister your modem. They can walk you through it on the phone, but it requires you have a computer directly connected to the SMC modem (a laptop or a desktop works just fine).

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