Scripting

The following message is displayed : During the installation a service was created that included an account name. The password for this account is required for the service to function. Do you want to enter the account password now. When I click yes I am requested to give the pasword of a builtin serviceaccount like NT AUTHORITY\NetworkService (not sure what the exact name of the account was)
I don't know this password.

At first sight I only find this link :http://www.itninja.com/question/service-account-name-and-password.

What do you advise ?