Group Text: Can receive, send pictures, but not send simple text to group. ATT Lumia 920 on TMo

[yodies]

Weird issue. I just got off the line with TMo support, and they gave me the following Access Point settings:

fast.tmobile.com in APN, MMS APN, connection name

http://mms.msg.eng.t-mobile.com/mms/wapenc in MMSC address.

I deleted the manual settings in Cellular.

I'm able to receive group texts, and I can send pictures as replies. But I can't send text. It is sent as a blank message to recipients. Had this working like a champ with Straight Talk. Don't know what I can do to fix it. Group text in settings/messaging is enabled as well.

Any ideas?

 

[Corepc]

Tmobile Issue join the crowd.

User's Reported it in 521 section

and here in Carrier Section

 

[yodies]

Thanks Corepc. Can't believe how hacky it is.