I have been getting the same problem lately and I am not rooted. I found that if I have a 1X connection or on wifi with 1 to 0 bars of signal I get failed text messges more often.
The weird part for me is that this happens when I have good coverage. Its usually when I have full bars on 3G. I have done the PRL and resets, still happens every now and again. I reset all of the messaging apps, and deleted all of my threads last night and it hasn't done it today so my fingers are crossed!
If you all are talking about SMS text messages (and not IM messages), then it does not require 3g to send. This is why you are able to send and receive SMS text messages while talking on your phone.
If you are having issues sending text, then you should also not be able to make or receive calls from that particular place. I have had no issues with SMS text, but have seen issues with 3g service dropping at places where it never dropped prior to 2.2.
I am rooted & running the leaked 2.2 (it works so well I see no reason whatever to switch to the OTA 2.2)
I use Handcent & have no problem whatever with SMS. I have had a message fail to send on rare occasions, but it happens like once a month & that happened with every phone I have ever owned.
Tried sending an sms to a friend. He has ATT.. msg failed to send. Also failed to send to his GV number. But it worked when I tried his work verizon number. he sent me a message on his ATT and I was able to reply... *shrugs*
I get the message that a text has not been sent maybe 3-4 times a day. But most days it means absolutely nothing as the person on the other end reply's to me with the answer to my questions. So even though it supposedly did not send they have received it.
The only fix for me was to get it working by hard reset...then backup apn... and everytime it happens ... reload the apn. Works for me.
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