My phone was having trouble sending messages. So I turned it off and then back on a few times and it sent all but 1. I went to the inbox and there was no message. So I took out the battery turned it on turned it off turned it on kinda thing and finally got the message to appear. Now however I have no network service at all on my phone.
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1 - make sure your SMSC isset to +15149931123 and make sure that this is the default number to use when replying to any sms you have received
2 - SIM CARD.....are you using the sim card that came with the phone or using an older sim card..i have experienced that issue..especially with 3G enabled feature handsets
3 - sms language (eng, french, ect...)...if your handset suuports the language of the recipient then the sms should get through the network seamlessly.. for example...if you have a friend in china and he sends you an sms in chinese characters and your handset does not have that language installed then you will have problems....
4 - if you fiddled with the settings...then i recommend doing a RESET SETTINGS ( WARNING !! this is different than MASTER RESET....refer to your user manual to get details )
let us know....thanks !