I a have some experience on this domain. Here were the deal for me :
• Streaming contents over IWP is supposed to work, as described on the fm12 instant web publishing guide. You can see p. 31 of this doc : http://www.filemaker.com/support/product/docs/12/fmp/fm12_instant_web_publish_en.pdf
• On the internet, it generally doesn't work because of the bug i reported here : http://forums.filemaker.com/posts/268bed5742
• On an intranet, it generally works. If you have problems, check first if your IE is configured to display PDF's. The Adobe PDF Reader plug-in mest be properly installed and activated.
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