: Open your Applications folder and double-click the newly added "Install OS X Yosemite" app to begin the actual upgrade. Download OS X Yosemite 10.10.5 Combo Update
macOS X Yosemite 10.10.5 is no longer receiving security updates. Using this operating system exposes the system to unpatched vulnerabilities. mac os x yosemite 10.10 5 download dmg
: Ensure your Mac is compatible with Yosemite before starting. : Open your Applications folder and double-click the
If a file ends in .cdr , simply rename it to .dmg . The format is identical; it is just a legacy naming convention from Disk Utility. : Ensure your Mac is compatible with Yosemite
: Open the Applications folder and double-click Install OS X Yosemite to begin the operating system installation. System Requirements
Q: Is the 10.10.5 combo update needed? A: Yes — the combo update includes fixes that may not be in the base installer; apply it after installation if you didn’t install a fully updated image.
Use Apple’s discontinued but still alive softwareupdate terminal command in older macOS versions. However, for most users, the easiest method is to obtain a verified DMG from a reputable archive like the Internet Archive (archive.org), where user apple_legacy has uploaded a byte‑for‑byte copy of the original 10.10.5 combo update and full installer.