Backup all data on the USB drive, as this process completely erases it. Step-by-Step Instructions Plug your USB flash drive into your Mac. Open (found in Applications > Utilities).
Plug your USB drive into the Mac and rename the flash drive to YosemiteInstaller . Open (found in Applications > Utilities ).
An Apple Disk Image (DMG) file acts as a digital copy of a physical installation disc. While modern Macs utilize the Mac App Store or Recovery Mode for updates, older operating systems require a standalone DMG file for several reasons: mac os x yosemite 1010 5 download dmg link
Note: This link downloads a file named InstallOSX.dmg . Inside this DMG is a package installer ( InstallOSX.pkg ) that unpacks the actual "Install OS X Yosemite.app" into your Applications folder. 2. The Mac App Store Method
"This copy of the Install OS X Yosemite application can't be verified" Backup all data on the USB drive, as
This comprehensive guide provides the verified direct download links, hardware compatibility requirements, and a step-by-step tutorial to create a bootable installer from the DMG file. Official Mac OS X Yosemite 10.10.5 Download Links
Apple has removed older OS X installers from the Mac App Store for versions prior to macOS Sierra. Consequently, the "Purchased" tab in the Mac App Store no longer shows Yosemite for download. However, trusted third-party resources continue to host the original OS X Yosemite 10.10.5 DMG for users who need to revive older hardware or perform offline installations. For security, always verify DMG files using their SHA256 checksum. Plug your USB drive into the Mac and
: This will install an app named "Install OS X Yosemite" into your Applications folder. It does not install the OS yet; it only prepares the installer. 3. Start the Installation Open your Applications folder.
If you downloaded the full InstallOS.dmg from Apple's support page:
Once the installer app is sitting in your Applications folder, you can create a bootable USB flash drive (minimum 12 GB required) to install Yosemite on any compatible Mac. Step 1: Format your USB Drive Plug your USB flash drive into your Mac. Open (Finder > Applications > Utilities). Select your USB drive from the left sidebar. Click Erase at the top. Set the Name to: YosemiteUSB Set the Format to: Mac OS Extended (Journaled) Set the Scheme to: GUID Partition Map Click Erase . Step 2: Run the Terminal Command Open the Terminal app (Finder > Applications > Utilities).