Hi...I imported all my videos and many of them do not show a thumbnail. They did in the PSE 9 in my old computer before I migrated to the new one. These are all the old home movies that I converted previously and they had thumbnails before. My other videos all show the thumbnails.
What is strange is that when I click on the "properties" it takes me to the actual file nd at that point shows the thumbnail on that file, but not the one in the catalogue.
We really don't have enough information to be able to help you.
What operating system is on your new computer? Have you gone to Windows Update and manually ensured you have even the non-critical updates? Have you ensured you have the latest version of Quicktime, and have you gone to the nVidia or ATI site to ensure you have the latest firmware for your graphics card?
How did your footage from one computer to the other? What kind of camcorder did this video come from?
Are you unable to see these thumbnails in Premiere Elements or in the Elements Organizer? Can you not see them even after you've created a new project and imported the footage into it?