I have yosemite 10.10.4 and was experiencing what I see as a common problem of not being able to access iPhoto. I as unable to upgrade it no matter how much i tried. I followed some instructions on here that said to remove it to the trash. Then look for a new version in purchases and download that. I deleted it to trash and restarted my macbook. I went to purchases and their was no iPhoto there at all. Nothing to download for free or for purchase. Now I am left with no iPhoto and just a question mark where the icon was. How do I get iPhoto bacK? I have macbook pro late 2011....please help. Apparently my photo library had already been migrated to photos???