the best you can get is a time and date stamped log of all incoming and outgoing messages when you go to the messaging usage section of your online account at tmobile.com.......as far as the content of those messages, you cannot view them without a subpoena from a lawyer or law enforcement
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I am a Sales Associate for T-Mobile. I have been with T-Mobile for several years and due to a lack of experience and go-getters in my district, I have seemed to taken the lead position in just about everything. I can usually answer questions and fix problems with just about everything. I am the Samsung rep, Nokia rep, Windows Phone rep, Blackberry rep, Small Business rep and probably know more about the future than anybody else you ask within the company. If you have a question about the future (upcoming phones or rumors), please know that I will speculate, but am in no way speaking on behalf of the company.
I cannot make changes to your account without verification.
As the other poster said, you can only view the time stamps for each message at my.t-mobile.com, however, T-Mobile does NOT keep the content in text messages stored in the system, and even with a subpoena, the content can not be retrieved.