I've searched this forum and have performed the necessary update to the PATH (system) environment variable but still receiving the "'javac' is not recognized as an internal or external command". I've even attempted to create and since removed the "JAVA_HOME" and "CLASSPATH" variables out of curiosity.
I should note: I do have Eclipse and I'm able to use Java with it. However, I would like to learn Java using the "HEAD FIRST JAVA". That is why I'm trying to do this.
One day I had the same problem, when I worked with different versions of JDK
It's because on the installation (I don't remember form what version exactly) change the environment variable "PATH", look the environment variable and find if you have something like a "C:\ProgramData\Oracle\Java\javapath" (if you used Windows).
If you see this value, remove it and check the value of PATH and JAVA_HOME again, reboot and try again.
The javac.exe file is part of the JDK, not the JRE.
that's very important, make sure you have installed a JDK not JRE