I got the following error while starting JBoss from a command line prompt today:
\'findstr\' is not recognized as an internal or external command
Check to see if you %SystemRoot% is evaluating (type set path into a command prompt, you should not see %SystemRoot%, but instead that actual path). If your path variable's (user, or systems) first entry begins with an %(an environment variable) this can cause an issue.
To resolve this, simply swap this first entry with anything else in your path that does not lead with an environment variable.