Update:12-10Source: network consolidation
I was sorting my pictures and wanted to add some new ones from a memory key. I tried drag and drop, but it took too much time. The little wheel for my mouse was rolling forever, my computer froze, and i had no choice to restart it. When it came on again, I went in iPhoto, and theyre were NO PHOTOS THERE. It says '0 photos'... i had them arranged and organized and now i CANT FIND THEM... WHERE HAVE THEY GONE.. !!! ??? THERE NOT IN THE TRASH? HELP

The Best Answer

As already pointed out when your library says there a zero photos in the library that's an indication that the Library6.iPhoto database file has been damaged and a new, empty one has been created. My experience and tests show that rebuilding the library in those cases will not recover your library. You'll need to start from scratch as follows:
Move the iPhoto Library folder to the desktop.,
Launch iPhoto and, when asked, create a new library.
One the new library is open drag the Originals folder from the old library folder on the desktop into the iPhoto window.
This will create a new library with the same rolls as the old ones. You'll lose your keywords, albums, etc., however.
For future protection against this sort of thing happening see the Tip at the end of my signature.
Do you Twango?
TIP: For insurance against the iPhoto database corruption that many users have experienced I recommend making a backup copy of the Library6.iPhoto database file and keep it current. If problems crop up where iPhoto suddenly can't see any photos or thinks there are no photos in the library, replacing the working Library6.iPhoto file with the backup will often get the library back. By keeping it current I mean backup after each import and/or any serious editing or work on books, slideshows, calendars, cards, etc. That insures that if a problem pops up and you do need to replace the database file, you'll retain all those efforts. It doesn't take long to make the backup and it's good insurance.
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