iPhone 5 won't send pic/video iMessages over xfinity router/modem

Just replying to say that I am having the exact same issue. Hoping to find a fix.

Tmajor -

I just ran the same tests with the same results you received. It definitely appears to be a conflict between IOS 6 and Comcast/Xfinity. I am using an iPhone 4S and a 3rd Generation iPad and both stopped sending photos over my home Comcast-enabled wi-fi once I upgraded to IOS 6.

I am sitting at my office right now on an independent internet connection having no issues over wi-fi - iMessage, MMS, and Email all send without problems.

Now if someone could just resolve the issue - QUICKLY!

Tmajor -

I will have to try that when I get home tonight. I recently updated to the Comcast/Xfinity modem & wi-fi router unit after my old modem crapped out. I also used to have a Netgear router (b/g/n) connected, so moving back to that solution isn't that big of a deal. I just hate dealing with the rigamorole that is Comcast Customer Service.

Thanks for sharing your headache and hard work finding resolution - I'm guessing this will solve at least one problem for quite a few people out there.

I'm having the same problem and its getting on my nerves!!!

It's what tmajor28 said!!!

Samething is happening to me. My temporary fix is turning off WiFi, send the MMS and then turning WiFi back on.

I wonder if we can port forward? 😕

I'm not only having the problem with MMS via iMessage on my Xfinity gateway but also my Chase Mobile APP as well! The APP lets me login when I'm on WiFi but I can not check any account details or deposit a check. When I switch off WiFi on my iPhone and go to cell data it all works the way it should. The Comast / Xfinity gateway definitely appears to be the issue!

Looks like I need to go pull my old Cable Modem out of storage and see if that will work. It's a good thing I never gave anyone the VoIP number that came with the bundle to anyone ...

I am now noticing the same thing with iMessage using Mountain Lion on my Mac. Hopefully Comcast can get this resolved. Strange issue.

So I went and found an old D-Link DCM-202 I had - plugged it in, called Comcast to add the modem MAC address info to get it to work. Was told by the Tech, that since I have an incredible Triple-Play rate from a promotion when they started phone service - if I ditched their wireless gateway for my D-Link modem, I would lose the phone service, and thus the great rate. When I explained the issues / problems I'm having - the Tech ...

1) didn't believe me, he said it was impossible that their gateway was the issue with MMS and Chase Mobile App. When I explained my troubleshooting approach - turn off WiFi on iPhone use Cell Data and everything works, he didn't have an explanation.

2) suggested they replace my wireless gateway with a Motorola modem / phone adapter. I told him I currently was only using their gateway as a modem attached to my Apple Time Capsule, I wasn't using their WiFi, so that should work.

The package is supposed to ship today, should arrive by the end of the week. We'll see if that works.

I have the exact same issue. I cannot send messages over iMessage with my Comcast XFiniti WIFI connection. I have a Netgear router providing my wifi but even connected directly to the Xfinity gateway it won't go through. I have no problem with iMessage over cellular.

Received the new Comcast modem this afternoon - an Arris TM722.

Short answer - solved all of my issues.

Long answer - the setup was a PITA!

Connected per included instructions - activated per instructions - no problem

iMac connected to modem via ethernet cable - no interent or mail problems

Connect modem to Apple Time Capsule - the problems begin.

No connection at all - no internet, no mail, nothing. Call Comcast - they don't know how to troubleshoot an Apple router. I ask them what the DHCP Setting should be - they answer "automatic". That's not an option - they don't know an answer.

Ended up calling Apple Tech Support - the solution was to reset the Time Capsule to Factory Settings, then reset it up using the exact Network Name and password so that everything would still connect.

After it was finally setup - I tested sending MMS from iPhone and iPad, as well as sending photo through Messages on iMac - all went as they should.

Finally checked Chase Mobile APP on iPhone - was able to login and deposit check as it should.

The problem HAS to be those Xfinity Gateways! All my problems were solved once it was out of my system.

I'm having the same issue as well. Xfinity and Apple have both been no help to me as far as troubleshooting. iMessage works perfectly at work over wifi but as soon as I get home I can't send pictures and they always go through as regular MMS messges.

I am having same issue....just got Xfinity have the ARRIS TG862.. my photos taken on iphone 5 will not go to the photostream and I can not log onto Chase mobile while connected to network...