Sorry for having to revive this old post, but I just came across this exact same problem you are describing. It says installing Acrobat 8 Professional is “allowed” AFTER installing Adobe Reader 9! It does not discuss adding Adobe Reader 9 after having Adobe 8 Pro installed. PS I just found at Adobe’s support on this question. That is the only workaround area I think is available to me, and I’m looking for some insight on how to get both to work together on Win 7 64bit if anyone has done so. I’ve researched Adobe Acrobat 8 and Reader 8 or 9 co-existence issues at and find conflicting answers, one of which is do not install Reader when you already have a full Acrobat version on your system. If there is no Reader then there is no access. It is not a plug-in issue – I think it is a programming issue that fails to accept any pdf application other than the free Reader. When I click on each pdf icon to view/print or download, I get the message insisting on installing the latest Acrobat Reader to access them. It occurs only when I log in to certain sites that have pdf files I need.

My current problem is not universal across all websites. It took me awhile to 1) update Acrobat 8 to 8.3 (which works fine with Win 7) 2) set it as a default and 3) get pdf’s to preview properly on almost all websites and within Win 7 explorer.exe and Outlook 2010. Thanks for responding – Acrobat 8 Pro and PDF Converter both have browser and MS Office plug-ins. Probably that one has no browser add on or plugin, so the browser does not use it.

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