I can open every files and authority but won't recognized me as Administrator. The only thing I know was, I haven't use my MacBook Pro for couple of months when our Internet Service change. I need help to override Terminal and get back normal.

Model Name: MacBook Pro (13-inch, Mid 2012) OS X El Capitan Version 10.11.6

Model Identifier: MacBookPro9,2

Processor Name: Intel Core i5

Processor Speed: 2.5 GHz

Graphics: Intel HD Graphics 4000 1536 MB

Number of Processors: 1

Total Number of Cores: 2

L2 Cache (per Core): 256 KB

L3 Cache: 3 MB

Memory: 4 GB (each of which accepts

a 1600 MHz DDR3 memory module and they are all in use.)

Startup Disk: Macintosh HD (167.71GB free of 498.91GB)

MAYBE IF EVERYTHING WILL BE BACK TO NORMAL THEN MAYBE ALL THAT WAS CRASH AND EVERYTHING WILL BE THE SAME...I AM JUST HOPE FULL...