Yosemite is only available for people who had downloaded it previously, otherwise it is no longer available.
You could probably upgrade to macOS Sierra if your Mac qualifies, otherwise you will be able to update to
Sep 22, 2018 The OS X Yosemite was released to the public on October 16, 2014, after been announcing it on June 02, 2014 at WWDC 2014. The Apple Inc. Has added a number of improvements and new features to the Download Yosemite Installer so that many Mac users have already upgraded to it by now. Jun 05, 2014 OS X 10.10 Yosemite (DP1) Installation Guide. Obtain a copy of Yosemite 10.10 DP1 - there are multiple files floating around the internet or you can use your developer account on. Jun 11, 2015 Hey All, Its been a while since Ive been here, but I got OS X Yosemite Final/GM 3/ PB 4 running on the E6420 via the following means. Credits: @Jake Lo - DSDT patches for HDMI audio, Most of the boot pack actually. XD@Pokenguyen - teaching me clover, giving me a.
Sep 02, 2014 Apple today released the seventh developer preview of OS X Yosemite bringing the latest build to 14A343f. The previous developer preview (build. OS X Yosemite DP7 1. Got 3 for OS X 10.10 and 2 for OS X Server. If you have a Developer account, you can add sub-accounts to get almost UNLIMITED codes.
Mac OS X El Capitan from here, Upgrade to OS X El Capitan - Apple Support
As both of these operating systems are a few upgrades newer than Mountain Lion you will need to prepare yourself.
Make sure you have enough RAM, 4GBs is minimum. Make sure third party apps you use now are supported under El Capitan or Sierra and have updates available, https://roaringapps.com/apps?platform=osx. Also make sure that any peripherals such as printers, scanners etc are supported under El Capitan and Sierra check with the manufacturers of these items for updated drivers / software etc.
iPhoto and Aperture if you had it are no longer supported by Apple in favour of their new Photos app.
About This File
Works under Mac OS X for 10.10.DP7
Clover r2697. (kext-dev-mode=1)
Chameleon r2391. (-v -f kext-dev-mode=1)
1. Restore BaseSystem.dmg to HFS partition.
2. Copy InstallESD.dmg/BaseSystem.dmg to (HFS partition) BaseSystem.dmg/
Os X Yosemite Download
3. Copy InstallESD.dmg/BaseSystem.chunklist to (HFS partition) BaseSystem.dmg/
4. Remove (HFS partition) BaseSystem.dmg/System/Installation/Packages
Os X Yosemite 10.10 Dp7 Update
5. Copy InstallESD.dmg/Packages to (HFS partition) BaseSystem.dmg/System/Installation/Packages
6.
OSInstall.mpkg replace to
/System/Installation/Packages/OSInstall.mpkg
Os X Yosemite 10.10 Dp7 Free
OSInstaller replace to
/System/Library/PrivateFrameworks/OSInstaller.framework/Versions/A/OSInstaller
7. Copy InstallESD.dmg/Packages/Essentials.pkg/System/Library/Kernels/kernel
to (HFS partition) BaseSystem.dmg/mach_kernel
or (HFS partition) BaseSystem.dmg/System/Library/Kernels/kernel
(use Pacifist v3.2.14, used for Chameleon only, not need for Clover)
8. Boot to (HFS partition) BaseSystem.dmg to install Mac OS X.
OSInstaller patch method credits to 落下爱@pcbeta