: You can download the OS X Yosemite disk image from Apple Support .
If you have previously "purchased" Yosemite (even for free) using your Apple ID, it may still be available in your tab within the Mac App Store. Open the App Store and sign in. Click the Purchased tab at the top. Locate OS X Yosemite and click Download . Download Yosemite 10.10 (NOT 10.10.5) - Apple Community mac os x yosemite 10.10 5 download dmg