1. Internet Explorer may display a blank page with a placeholder icon instead of displaying a Portable Document Format (.pdf) file with Adobe Acrobat Reader. This behavior occurs because the Uniform Resource Identifier (URI) to the .pdf file does not end in ''.pdf'' (for example, the file is opened by using script or the file is dynamically generated) and the content-type header (Multipurpose Internet Mail Extensions [MIME] type) that is returned by the server is ''unknown/unknown''. Previous versions of IE open Adobe Acrobat Reader as a plug-in, but IE6.x does not support Netscape-style plug-ins, which BTW, could happen with any unrecognized plun-in, [Q305153] and [Q306790].
Note: The article [Q555027] explains that when you try to connect to web site by using Internet Explorer 6 or Internet Explorer 6 with Service Pack 1 - it may open with blank page, instead of web site and the problem could be that some dll's didn't register themselves. Check the registering process in this article as well as downloading and following the instructions for ''IEFix'' - a general purpose fix for Internet Explorer (Win 98/ME/2000/XP).
2. When Acrobat or Adobe Reader is installed on a system that includes a browser, the browser is automatically configured to open PDF files within the browser window and the ActiveX plug-in files are installed. However, you can configure your web browser to open PDF files either in the browser window or in a separate Acrobat window.
? To open a PDF file in Internet Explorer, choose File, Open (or Open File).
a. Click the Browse button, choose All Files from the ''Files Of Type'' pop-up menu, and then navigate to the location (path) of the PDF file to be opened.
b. Select the PDF file, and then click Open, which then opens in Internet Explorer.
? To configure the browser to use Acrobat or Adobe Reader to open PDF files:
a. Quit Internet Explorer or AOL.
b. Start Acrobat or Adobe Reader.
c. Choose Edit, Preferences and select Internet in the list on the left.
d. Deselect Display PDF in Browser, and click OK.
Note: If Acrobat or Adobe Reader displays a PDF file from the local hard drive but won't display a web PDF file, the web server has a problem serving the file. The only recourse is to contact the webmaster of the site from which you found the PDF file and tell them they have a site problem.
3. Otherwise, check the Adobe ''Support'' site.
My computer has Windows XP Media Edition 2005 and I have Adobe Reader 7.0 installed on my computer. I can save PDFs and open them in Adobe Reader, but I cannot view PDFs online. When I try to, IE (6.0) freezes and crashes.
I know that I should be using something other than IE, like Mozilla Firefox, but when I installed that and opened the browser, it just said "looking up (webpage)" forever and did nothing. Also, sometimes when I tried to open it, nothing happened. I opened up Windows Task Manager to see what was going on, and it showed between 5-10 firefox.exe images. I have run virus scans and spyware scans and still have both problems.

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