Config.fpw is read only ? It is usually caused by a rights issue, but it is 98 so it shouldn't be a problem.
Does config.fpw existin the app directory ?

>A customer of mine installed my software in windows 98
>
>When he tries to execute to software, the message below is shown:
>
>"The resource file is not valid.
>Overwrite it with a new one ?"
>
>When clicks yes, a fatal error message appears
>
>What can it be ?