** General to consider whether there are other people or recently modified its own environment variables, this error often is because the environment variable settings error. **
1. First to get create or open bash_profile permission to enter the command line:
export PATH=/usr/bin:/usr/sbin:/bin:/sbin:/usr/X11R6/bin
It can be achieved bash_profile temporary use.
2. Type cd ~ / # to enter the current user's home directory
3. Create bash_profile execute the command:
touch .bash_profile
4. Open and edit bash_profile execute the command:
open .bash_profile
5. This opens a notebook, displays path has already been configured, modification notepad, delete all, can be a useful backup, coupled with the command line to solve
export PATH="/usr/local/bin:/usr/local/sbin:~/bin:$PATH"
PATH="/Library/Frameworks/Python.framework/Versions/3.6/bin:${PATH}"
export PATH=$Path:/usr/local/mysql/bin
6. Save, command + s
7. In this command line input update command
source .bash_profile
8. Then enter sudo spctl --master-disable