Preview pane and thumbnails don't work under Windows 7

Hi,

last week I purchased and installed CorelDraw X4. After I had watched the video tutorials I wanted to try out the preview function in the Windows Explorer which should work with Vista and Windows 7. A double click starts Corel X4 properly, but the preview or the thumbnail function doesn't work (message "no preview available"). Curiously the Corel paint Fotos work in the preview pane. Only cdr-files aren't previewed.

In the scrapbook the cdr files are displayed correctly.

Does anyone has an idea how to activate this preview function?

I thank you very much from German!

Gonzo

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