Have spent some time on this checking out the settings given for the fix and just as everyone else on Sprint, no go!
Flashed back to factory to test and of course, it worked. After doing some digging, I exported the full Arcsoft Registry key to compare to HTC Messaging. One thing I noticed, Arcsoft is using
http://mms.sprintpcs.com as the MMS server and using X-MDN in a different reg key. The UA profile and UA are using Sprint settings in the factory and using HTC in HTC messaging. The HTC settings are pointed to a valid website xml file. At the end of the file, it states "Copied from Rhodium-1.0."
So, of course, I reflashed EnergyRom 2.5 21884 12/17 and changed the Arcsoft settings and Jataayu Settings to reflect only the above website for MMS and added the MDN info as it was in Arcsoft on factory. Still no go. I have attached the reg export and the xml file that HTC Messaging is using as the UA. Any ideas???