These 'intermittent' problems are difficult to solve. I mean, what is the difference between a site where a PDF file loads properly inside the browser window, and a site where it fails?
Can she give an example of a site where this fails? Then maybe we could check.
How about a workaround? On a web site where clicking a link to a PDF file fails to display properly, backtrack, (back button on the browser), then right click the link and download to the Desktop. If she has Adobe Acrobat installed, or at least a PDF Reader which she should have if she has the browser plugin, then opening the file from the Desktop should work. If the PDF is still blank, then that is a fault with the web site.
Be sure to ask her to scan all downloaded PDF files before opening.
Hope that helps.
Mark
A friend is running Windows 7 on an HP desktop with 3GB of RAM. For work she goes to a web site that has many links to .pdf documents. Sometimes if she clicks on the links the .pdf file displays just fine. Other times, with the same link, just a blank pop-up window appears with Adobe Acrobat in the title bar of the window. This happens often enough to be a problem. Does anyone have any thoughts as to why this is occurring? Thanks for any feedback.

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