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A common culprit of excessively long boot times is a process called DSMOS (Don’t Steal Mac OS) that runs every time you start your Mac. DSMOS was implemented by Apple to check that OS X is running on genuine Apple hardware, and not on a Hackintosh or the likes. Consequently, this process can take anywhere from half a second, to over 30 seconds during the boot process.
To fix this, you need to change the owner of the / directory to Root.
1. Open Terminal, located in /Applications/Utilities
2. Copy and paste:
cd /
sudo chown root:admin /.
into Terminal, and press Enter
3. Type in your password if prompted, and press enter again.
Reboot your Mac. If you want to see all the processes that run during startup, hold down Cmd+V as soon as you hit the power button. Look for the line “Waiting for DSMOS…”, which is the process that we’re fixing. The following line will be “DSMOS has arrived”, which indicates the process has been completed.