In Exchange 2013, resetting the password for users can be difficult. It might be missing or you may not see the option when you click on a USERNAME.

Luckily, this isn't difficult to overcome. I found the steps here:
http://www.mustbegeek.com/reset-user-password-in-exchange-2013/

  • -click PERMISSIONS (on the left-hand side).
  • -click ADMIN-ROLES (at the top).
  • -double-click ORGANIZATIONAL MANAGEMENT (in the middle).
  • -find the ROLES section.
  • -click the + (plus-symbol).
  • -find RESET PASSWORD (in the list).
  • -click ADD (at the bottom).
  • -click OK > SAVE.
  • -logout of EAC.
  • -login to EAC.

This should enable you to change the passwords within EXCHANGE EAC.