The command prompt is a very useful feature in the system, and we have to look at all of the computer's IP addresses and so on, and we can enter commands in the Command Prompt window and know the results. But if you appear, whatever command you enter is a reminder that you are not an internal command or an external command. If you guarantee that the order is correct, then the setup of the system is changed by someone.
1
The problem is because the value of path has been changed.
The path value is basically where you enter the command call.
2
Where path is located
Right-click My computer → properties → advanced system settings → environment variables
3
Be changed for example:
What is inside the path value? For example, some software will be changed to C:Program Files (x86) Stormiicodec; C:Program files (x86) Stormii, also remove the real system file address.
4
Workaround:
The value of path plus%systemroot%system32;%systemroot%;
The above is about the Win7 command prompt in which the input commands are invalid how to do. Through the above method can be solved. The problem I have encountered is solved by this method.