There is another, more subtle, but simpler cause of this problem.
After multiple searches on the Internet and many hours with MSFT support, however it may seem, it may seem that the main reason for my "SharePoint will not open PDF documents" problem was actually an extension of Adobe / on. The symptom was an Adobe "msgstr" error error after clicking a PDF list item in a document library. Criminal, Adobe extension / addition: "Adobe Acrobat SharePoint OpenDocuments Component."
I do not know how this was established. What I know (finally) is that this component actually does the exact opposite of what its name implies, that is, it apparently prevents PDF documents from opening when you click in a SharePoint 2010 document library.
After various unsuccessful attempts to solve this problem (including changing the settings of the “Browser File Handler” on the web application server from “Strict” to “Permissive” and other corrections proposed below and elsewhere on different blogs and websites), nothing fixed the problem until we disable this Adobe extension / add-on. Then the problem is solved.
Please note that you cannot see this component in the "Tools> Manage Add-ons" list until you try to open a PDF document from the library: apparently, the add-in is not activated (the list will not be displayed in this) until it is attempted attempt to "open". SO - if at first you do not see the specified component, try opening the PDF file and checking the list again. If this component appears, disable it and your problem will most likely disappear.
Obstacle, at best; or, even worse, is actually vile on parts of Adobe ...?
Anyway, I would like to know how to open a PDF file in a separate browser tab in IE and shift the active tab. If anyone can help with this, please let me know! There are no special encoding solutions, PLEASE!
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