Introduction: Why Yosemite Still Matters
"This copy of the Install OS X Yosemite application is too old": If you see this error, it’s usually a date-check conflict. Open Terminal during the installation and change the system date to 2015 (e.g., date 0813000015) to bypass the expired certificate.
Mount the Image: Double-click the downloaded .dmg file to open it.
Use Terminal: Use the following command (assuming your USB is named "Untitled"):sudo /Applications/Install\ OS\ X\ Yosemite.app/Contents/Resources/createinstallmedia --volume /Volumes/Untitled --applicationpath /Applications/Install\ OS\ X\ Yosemite.app
Because Apple’s official certificates for Yosemite expired in 2019, even the official installer requires a date trick to run. The largest verified repository for the Yosemite 10.10.5 DMG is the Internet Archive.
If the user previously "purchased" (downloaded for free) Yosemite while it was current, it may remain in their purchase history.
Legacy Hardware Support: It runs smoothly on older machines (like the 2008-2009 iMacs and MacBooks) that struggle with newer, more resource-heavy OS versions.
Conclusion
Introduction: Why Yosemite Still Matters
"This copy of the Install OS X Yosemite application is too old": If you see this error, it’s usually a date-check conflict. Open Terminal during the installation and change the system date to 2015 (e.g., date 0813000015) to bypass the expired certificate.
Mount the Image: Double-click the downloaded .dmg file to open it. mac os x yosemite 10.10 5 download dmg
Use Terminal: Use the following command (assuming your USB is named "Untitled"):sudo /Applications/Install\ OS\ X\ Yosemite.app/Contents/Resources/createinstallmedia --volume /Volumes/Untitled --applicationpath /Applications/Install\ OS\ X\ Yosemite.app
Because Apple’s official certificates for Yosemite expired in 2019, even the official installer requires a date trick to run. The largest verified repository for the Yosemite 10.10.5 DMG is the Internet Archive. The Complete Guide to Mac OS X Yosemite 10
If the user previously "purchased" (downloaded for free) Yosemite while it was current, it may remain in their purchase history.
Legacy Hardware Support: It runs smoothly on older machines (like the 2008-2009 iMacs and MacBooks) that struggle with newer, more resource-heavy OS versions. Mount the Image : Double-click the downloaded
Conclusion
