I guess that I have probably made some kind of error myself - but the problem is that it seems that DO (4497) will only generate thumbnails for my MTS files (AVCHD full HD) nr. 00000.MTS and up to 00126.MTS.
From 00127 and up it only shows windows media player icon...
I do not remember if precisely the 127 files by some strange chance are the files from my first days video recordings - but anyway.
The thumbnail view is set to 282x162 and I have a 6 GB thumbnail cache and done reset/empty and restarted DO and also rebooted the laptop several times.
The JPG thumbnails in the same directory are shown correctly.
The JPG and MTS files are not imported by some (strange) camera software but just copied from the SD card put into the laptop.
The MTS files do play well in the media player - (and in Sony Vegas Pro editor too) - just the Thumbnails are missing.
I have tried to copy the last 30 MTS files into another directory - but (also) here DO shows only the media player Icons.
Have tried to change to VLC player as default player program too - but still no thumbs.
Have tried from 1 and up to 3 thumbnail threads.
Windows 7 Home edition 32 bit with all updates.