Yosemite made all my photos dissapear
How about rebuilding the library? Sometimes files can become corrupted.
iPhoto 6 and later: Rebuilding the iPhoto library - Apple Support
Which version of iPhoto did you upgrade from? What happens when you try to launch iPhoto? Do you get any warnings, when iPhoto upgraded the library?
I have tried everything but my library is empty.
What have you tried already?
Where did you store your iPhoto library? On an external drive or your system drive?
iPhoto will create a new, empty library, if it cannot open or find your previous iPhoto library.
If you upgraded from iPhoto '08 or earlier, the iPhoto library needs to be prepared with iPhoto Library Upgrader. See this link: iPhoto '11: About the Library Upgrader
If you got error messages during the upgrade of the library, restore your iPhoto Library from your most current backup.
After installing yosemite and the latest version of iPhoto all my photos want missing. I have tried everything but my library is empty. Why on earth apple changed iPhoto. It wasn't broken who fix it. I am seriously consider to get ríd of my iMac
