InstallAware

Our installation program requires user to enter a password and that password has to match password complexity (in particular the minimum length required) of the Window OS (windows command 'NET ACCOUNTS'). What we would like to do is to show the minimum length in the dialog box as a text on the dialog that prompts user to enter the password. This would help user to know how long the password should be. Is there an API within InstallAware that would get me the minimum password length from the Windows?

No, unfortunately there isn't any built-in method for this available. You should develop your own one, as a plugin, or implemented in an external DLL or EXE.