For some reason I have not been able to text certain verizon numbers since Sunday. My girlfriend is the main person I'm having this problem with and every time I text her I get the message, "error invalid number please re-send using valid 10 digit mobile number or valid short code." She can send me texts and she can receive texts from any phone but an iphone. I say this because I have used my iphone, my brothers and also a friends iphone and all of them come back with the same message. if I use other phones it comes through just fine. I have searched and tired everything from reformatting my iphone, resetting network settings, deleting the contact info multiple times and ways, and I even had a new sim card put in. Does anyone have any ideas how to solve this problem?