Getting error when update mac os from Mavericks (10.9.5) to El Capitan (Latest version) I want to update my mac mini OS from Maverics to EI Capitan.

When i click on Get button at that time it will give a error message. For better understanding i attached screen shot of the error message.



Also i attached screen shot of the mac mini configuration.



I tried with removing cache folders from the /private/var/folders path but not working.

In above path i found folders, which name is 7s and zz. Also remove the folder which name is com.apple.appstore for remove the temporary files.

Please provide appropriate solution for upgrade the mac os.
After formatting mac OS solving the issue.
Do reinstall OS 10.9.5 (Maverics) from safe mode of mac OS.
After reinstalling upgrade OS EI Capitan from app store, this is the only solution which i done in my case.