I’ve tried to install OS X Sierra on my MacBook Pro 13-inch (Late 2011) from USB and faced this error: “
The installer payload failed signature check“.
The problem is The installer checks the date on the computer. If the date isn’t current, you get the error above. The fix involves correcting the date on your Mac.
To fix the issue, open the Terminal from Recovery Mode (Utilities > Terminal) and check the current Date with the command
If your Mac is connected to the Internet, you can check online for the current date and time. You can do this by typing at the prompt
ntpdate -u time.apple.com and then pressing Enter (Return) button.
If you don’t have an internet connection
At the prompt, type
date [numerical], with
[numerical] being the representation of the current date.
It’s simple to calculate the
For example if the current date is
December 13th, 15:01, 2016, then
[numerical] will be:
12 – number of month December,
13 – day of month,
1501 – time 15:01
16 – the last two digits of the year.
If you’re facing the difficulties to calculate the
[numerical], please feel free to ask me in the comments.