>As I am developing .NET application.
>one of my client challenge me that WHY our company not use "JAVA" ?
>My boss need me to list out what is the advantage of .NET and How it can affect the cost in office ??
>e.g Java didn't need license fee ? .NET (if using MSDE, the database is free)
>PDF work very well with .NET ??
>
>I really don't know how to do it.
>Please give me a help

Is your client qualified to understand the reasons why one tool would be chosen over another? 99.9% of the client's who ask this question ask out of ignorance. Either they've just read an airline magazine or one of their buddies at the fitness club brought up the subject.

Do yourself a huge favor and DON'T GIVE AN ANSWER. Once an answer is offered up, the client will then spend his time trying to tear down your reasons. The only way to win in this situation is to either switch to the tool that they asked about, or deflect the question forever.