I solved the riddle of my interop unlocked Titan I and my wife's interop locked Titan I. Under the HTC Connection Setup app, use "Consumer Cellular" - it is an AT&T MVNO and will input AT&T's MMSC settings with this selection. Everything under settings>>>cellular>>>APN is to remain blank. As many of know with the Titans there is no way to manually make changes to MMS/MMSC settings under the Windows Phone 7.x platform.
Thursday - April 10, 2014: Straight Talk now has new TracFone SIM cards for all their GSM customers that now have added 4G LTE to devices that have that radio in them. The new SIM does change the APN settings and currently working to find a solution that makes MMS impossible once again. This does not apply to Window Phones 8.x devices; these devices have blanks to fill in MMS settings; this is applicable to Windows Phone 7.x.
Thursday - April 10, 2014: Straight Talk now has new TracFone SIM cards for all their GSM customers that now have added 4G LTE to devices that have that radio in them. The new SIM does change the APN settings and currently working to find a solution that makes MMS impossible once again. This does not apply to Window Phones 8.x devices; these devices have blanks to fill in MMS settings; this is applicable to Windows Phone 7.x.
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