PDF-Thumbnail donot correspond with actual files

Weird thing: in thumbnail view, the PDF-files show random images, but not one that correspond with the file.

e.g. a thumbnail shows the cover of computer-magazine, but the document is in fact about govt. info regarding passwords
or a thumbnail shows a scanned page of an old magazine, whereas in fact it is a pdf with a screenshot of outlook settings.

I shortly checked, images are fine, video (wmv, mp4, etc) also fine.

The PDF thumbnails they are mixed up.

some examples, left the thumbnail (title is correct).

Opus doesn't generate PDF thumbnails itself -- it asks the system PDF handler to do so -- so that is a bug in the PDF software you have installed.

Adobe Reader has an issue like that, where it can get confused if asked to make thumbnails from multiple threads at once. You should be able to fix it if you install my Fixes for 64-bit Adobe Reader. (If you're already using them, it might be due to an old version. The fix for this was added later, although it's quite old now.)

Setting Opus to only use one thumbnail thread may also avoid the problem (under Preferences / File Display Modes / Thumbnails), although it's not ideal, obviously.

Note also that the shell caches PDF thumbnails, so you may need to clear the shell thumbnail cache after changing things to get correct thumbnails for files that have already been generated. Copying the files to a new directory for testing is best, as then you don't have to worry about caching. (Installing my fixes should clear the shell thumbnail cache for you automatically, if you decide to go that route. Also, you should not normally need to clear the Opus thumbnail cache, unless you have installed a 3rd party Opus plugin that generates PDF thumbnails -- if you have done that then that changes things as it may be involved with the problem.)

Many thanks for the detailed reply.

I am using Acrobat Pro XI (v11.0.06.70, latest version)
It is installed on a different partition.
Frankly, I don't know whether it is 32bit or x64, no way to find out.
It is not in the 'About'-box and I vainly tried to figure this out using some systemtools.

That aside, also I am a bit unsure whether the solution offered will also fix the problem
in the case of Acrobat Pro (seems it refers to Acrobat Reader only?)

On adobe.com/support/downloads/ ... ftpID=4025
I read about Adobe PDF iFilter 9 for 64-bit platforms and Adobe offering a PDFiFilter64installer.zip
Then again, that refers to version 9 of Acrobat/Acrobat Reader.

You are offering "Adobe_Reader_x64_fixes_v3_001_noinstaller.zip" - which I downloaded,
but - in view of the above - not yet applied.

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Later:

applied your Adobe_Reader_x64_fixes_v3_001_installer.zip
matter solved!

wonderful, thank you so much!

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