Daemon tools could not be opened

My notebook computer is using Windows Vista.I have instaled the Daemon tools Lite4.30.03264 Bits.When I tried to use it . A warnin statement said:`Please use local administrator account to run Daemon Tools for the first time'.I used the administrator account to log in.But the same statement occured again.I have just bought the computer for one day!How can I fix this problem??????