IF ERRORLEVEL 1 ECHO error level is 1 or more to check for errors
in your batch/command line scripts.
DO NOT use
IF %ERRORLEVEL% NEQ 0 ECHO error level is not equal to 0.
Most of the time
%ERRORLEVEL% will be what you expect but it isn't guaranteed.
%ERRORLEVEL% is simply an environment variable like any other. It just happens to fallback to returning the
ERRORLEVEL value if an environment variable with that name isn't defined.
This is how I lost about an hour of my morning. Fortunately Google guided me to this excellent post and saved my sanity.
%ERRORLEVEL% is not the same as