Did you root your captivate while on the att network?

A possible reason why this is happening, cm10 that your running is meant to be for the att network and not the straight talk/track phone network.

But I'll dig deeper and see what I can find.

DS

 

Do you have a phone apn and a wap apn? Your settings match what is found here, but a couple other users had to tweak it a little
http://forum.xda-developers.com/showthread.php?t=1856574

This user's mmsc is different:
http://forum.xda-developers.com/showthread.php?t=1638290

 

Yess, you must make sure the MMSC settings are changed as well like in the second thread linked above.

good luck

 

hi i have an htc one x with straight talk AT&T NETWORK i tried some different apn with half of what straight talk says and some setting from att you might try this one it worked for mine
name=straight talk
APN= ATT.mvno
PROXY= proxy.mvno.tracfone.com
PORT=80
NEXT 3 SPACES= NOT SET
MMSC= mmsc.att.net
MMS PROXY=proxy.mobile.att.net
AUTHENTIC TYPE=not set
APN TYPE=default,admin,fota,mms,supl,hipri
bearer = unspecified

also if you have the byop and using the net 10 sim card it should be the t-mobile apn and not the at&t. thats the thing at&t and straight talk split that's why you cant get them anymore straight talk/AT&T sim cards only the t-mobile net 10 and in some areas t-mobile service is not good at all HOPE THIS HELPS

 

TRY THIS APN
hi i have an htc one x with straight talk i tried some different apn with half of what straight talk says and some setting from att you might try this one it worked for mine
name=straight talk
APN= ATT.mvno
PROXY= proxy.mvno.tracfone.com
PORT=80
NEXT 3 SPACES= NOT SET
MMSC= mmsc.att.net
MMS PROXY=proxy.mobile.att.net
AUTHENTIC TYPE=not set
APN TYPE=default,admin,fota,mms,supl,hipri
bearer = unspecified