New PDFs not showing thumbnails anymore

[Irriducibile]

Hi

For a few days, newly downloaded/copied PDFs don't show a thumbnail preview anymore. The weird thing, however, is that older PDFs still do. There is a cutoff date from a few days ago; older ones have a preview, newer ones don't. But no idea what happened there, probably some update.

These things have NOT helped:
- Enable preview in Adobe Reader settings
- Use Fixes for 64-bit Adobe Reader preview handler and thumbnails

Can anyone advise what else to do?

Thanks

 

[Irriducibile]

Okay, there's been a new development: I found out that the thumbnail appears if I place the pdf in the recycle bin. Wtf? So in the recycle bin, thumbnails are visible, but in the explorer/desktop not. And if I put a pdf in the bin and then back to the desktop, it remains visible. So the bin kinda works as a thumbnail generator, whereas the desktop is a thumbnail killer. So that's a workaround, but can't be a permanent solution.

That's just messed up...

 

[Trouble]

Have you considered rebuilding your icon and thumbnail cache to see if that will help?
There's an automated tool to help with this here https://www.thewindowsclub.com/downloads/TICR.zip

Further information about the process here

Thumbnail and Icon Cache Rebuilder for Windows 10

Thumbnail and Icon Cache Rebuilder for Windows 10 is a portable freeware that will purge, clear, and delete your Thumbnail and Icon Cache in a click.

www.thewindowsclub.com

 

[Irriducibile]

Yes I did that several times but it didn't help. It only made all thumbnails disappear.

However, now there's been a new-new development.

Doing the "bin workaround", I can see the thumbnails again (e.g. after clearing icon cache), but only inside such an ugly white square:

How do I get rid of those? I remember having the problem a year ago when I bought the laptop. I think (though not sure anymore) I solved it with this advice (about the alpha channel). But now even that one won't work.

So now my 2 questions are:
- How to get rid of the white square?
- Why do I get a preview in the recycle bin but not on the desktop? What's the difference?

Thanks