The issue occurs because of how the User must change password at next logon option is implemented in Active Directory. A user is forced to change password at next logon if the Password Last Set property is set 0 or Unspecified value, and the Password never expires option is not enabled. When users are created in Active Directory, their Password Last Set property is set to the Unspecified value by default, and if you don't check the Password never expires option, users will be forced to change their passwords at first logon.
You can work around this with the help of a Property Pattern. Property Patterns allow you to specify a default value for a property. If you create a Property Pattern that disables the User must change password at next logon option for new users, the option will be disabled for all new users affected by this Property Pattern. For information on how to create a Property Pattern that sets default values for Account Options, see the following tutorial: http://adaxes.com/tutorials_Simplifying ... gUsers.htm. You can use it as a guide. On step 5, specify a value with the User must change password at next logon option unchecked.