Once an account is created on the phone, how can you change the password to that account?
You mean the google account or the HTC account?
The google or HTC.
The google account of the phone is linked to the email you typed in when you synched your phone. I suppose that if you change the password on that email, that would change your password of your phone's google account.
You can change your google password. Once you do and go onto your phone and try to access gmail or the android market its going to ask you to login again.
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