Any time your password for the Transtar network changes (The password to logon to your computer) you also need to update your password in Global Protect.
Global Protect should prompt you to make this change with the following popup-
Your username is always the same as the username used to logon to your computer (Generally your first initial and last name)
Your password is always the same as that used to logon to your computer
Portal always needs to be: dgprotect.transtar1.com