I'm in the process of setting up a new laptop with Windows 7 Enterprise and I'm having two issues:
Image previews/thumbnails are not displaying in Explorer.
Most of the files I've copied from my old system have a grey "X" overlay on the icon.
I suspect these issues are related, but I really don't know. As best I can tell the grey "X" has to do with files being archived to tape (?), but I have no idea why this is happening. I've ensured that "Always show icons, never thumbnails" is not set. I've deleted the cached thumbnail files. Still no luck.
Here's a screenshot that illustrates both issues:

Any ideas?