I finally got it to work after nights of no sleep and dreams about it. I was previously successful on the 3g with a post from this forum but failed on the 3gs time after time after following many different threads. I mixed and matched ideas, threads, sim cards and finally got it to work flawlessly and been working for the last 24 hours. I can send Pictures and Video. I had given up on MMS on the 3GS but had a dream about mms so I kept trying lol.
Here is what you do.
1. Update the carrier file on your iphone then reboot your iphone. Once iphone reboot update carrier file again and remove sim.
2. Setting-General-Network-Cellular Data AND ENTER ON ALL FIELDS *****except first line in voicemail enter "acds.voicemail"****
APN: wap.cingular
Username:
WAP@CINGULARGPRS.COM (CAPS
Password: CINGULAR1 (CAPS)
MMSC: mmsc.cingular.com
MMS Proxy: 66.209.11.32
MMS Max Message Size: [leave blank]
MMS UA Prof URL: [leave blank]
HIT the home button then leave iphone alone DO NOT REBOOT!!!!
3. insert sim into an mms capable att phone. Make a 1 minute phone call (No need to log into ATT or call ATT).
4. Go to
https://mymedianet.wireless.att.com/ (on your computer) and register for media net while sim is in mms capable phone if it give you an error saying that phone is not capable of media make another phone call until it lets you register it. It will tell you that a text was sent to that phone with a 4 digit pin and it will ask you for the pin. You will receive a text with the pin enter the pin on your computer then hit continue. It will ask you for an email if its the first time you register if it does enter your email then hit continue. After that send a picture (mms) from the non iphone.
5. Log into ATT and under your number if you still see an iphone manually switch it to the mms capable phone. Go to features and change it to a regular text plan not an iphone text plan. (If you currently have family iphone text you will have to change it to the 1500 text plan then change it to unlimited family text (not iphone text plan)
***Your account must say under features "Messaging Unlimited for Families - Shared" (NOT Iphone Text)
6.Remove SIM from non iphone and insert it into the iphone. DO NOT REBOOT IPHONE and also DO NOT GO INTO CELLULAR DATA SETTING. You will now have MMS on your iphone and it wont stop working unless you mess with setting or reboot phone.
I have tried it many times and never fails. Please Sticky......
BTW I got it working flawlessly to where I put it on my girls phone as well as my dads and friends.