I receive the above error message when I attempt to send a message to a particular phone number. I have been able to text to this number before and it suddenly stopped working. The owner of the phone number assures me that I am not blocked. I am using the SMS message app that came with the phone.
So far I have:
1. Updated the software (PRL update) *228 option 2. Update was successful. Powered off/ back on. No change.
2. Deleted all threads that included the destination phone number and created new thread. No change.
3. Removed battery for 5 minutes. Rebooted. No change.