Thumbnails disappeared

[Athena]

I was going along quite happily with my PDF thumbnails in the Vista Windows Explorer until I made the mistake of doing some experimenting with Adobe Reader and they disappeared. I've removed the Adobe Reader, re-registered the PDF-Xchange shell extension and tried cleaning up my thumbnails but no joy: the thumbnails are still MIA.

What do I have to do to get my thumbnails back?

Thank you.

UPDATE: When I set a different PDF Generator to be default viewer, my thumbnails reappeared! I don't get it; why can't the PDF-Xchange Viewer be the default if I want thumbnails in the explorer?

[Ivan - Tracker Software]

Can you export and send me a piece of registry by the path: HKEY_CLASSES_ROOT\.pdf ?

[Athena]

How do you want me to send it: Attach a file or send to an e-mail address? Do you want an actual REG file or would a text copy be adequate?

[Ivan - Tracker Software]

You can send me to Ivan@tracker-software.com
Please send as .reg file - would be easier to me to find what I'm looking.
Also, please export the registry HKEY_CLASSES_ROOT\Value, where Value is the default value shown when you select HKEY_CLASSES_ROOT\.pdf item into regedit.
It can be AcroExch.Document, or PDF-XChangeViewer.1, or something else.

[Athena]

Well I've been experimenting with so many PDF generators this month, my registry in this area may be trashed. I installed the PDF-Xchange driver and viewer on a clean Win7 machine and I have no problem at all with the thumbnails. I guess I need to take a closer look at what may be different on some of my machines