Problems with Lightroom Library and...

I have imported various photos in my Lightroom library but if I try to search some specific photos with the Keyword Tags or with Metadata Browser or also when I click on ''All Photographs'' to see all the photos together, no photo is showed on the grid.

Does anyone know how to solve this problem? I have windows Vista; is it maybe a Vista bug?
Problems with Lightroom Library and...
It's more likely that you have a filter set. Double check that, and you'll probably see the images.
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%26lt;br /%26gt;MacBookPro 2 Ghz Intel Core Duo, G-5 Dual 1.8; Canon DSLRs
Problems with Lightroom Library and...
Thanks

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