Unless your have some sort of process you are calling ON THE CLIENT machine itself, it shouldn't matter if they are connecting via Linux, Windows 98, XP, ME. (Within reason of course)
Simply put, all the client does is render the page through a web browser, the server does all of the "hard work".
What is different between the machines?
Different networks?
Can your 98 machines "see" the IIS box?
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I will only tell you how to do it, not do it for you.
Unless, of course, you want to hire me to do work for you.
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Read this if you want to know how to get a correct reply for your question:
http://www.catb.org/~esr/faqs/smart-questions.html
^^Took that from planoie's profile^^
^^Modified text taken from gbianchi profile^^
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