By default, the value of password-generator in Default Password Policy is Random Password Generator, and then if I try to set a password for a user, I'll get an error shows I cannot provide a password.
But in my case, I want the user can set his/her initial password when the account is created. So, how can I disable the property and just let user set the password?
The password-generator is only used when trying to set or change a password with ldappasswordmodify and no new password is passed as parameter.
If you are getting an error when trying to set a password for a user, it is not due to the password-generator. It's something else, and the error message that you can find in the Access log should be pretty explicit.