i can't update security update

Try downloading it & installing it in Safe Mode...

https://support.apple.com/kb/DL2023?viewlocale=en_US&locale=en_US

Safe Boot from the HD, (holding Shift key down at startup), does the problem occur in Safe Mode?

zaira_ileana Said:

"i can't update security update: I have tried many times to update the new security update unsuccesfully, I need help, please..."

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