I\'ve tried installing Maven to Windows 7 with poor results. Some basic info:
Maven installation directory: C:\\Program Files\\Apache Software Foundation\\ap
C:\\Program Files\\Apache Software Foundation\\ap
Get rid of the env variable M2_HOME. It is not used by maven 3, and in fact, confuses it. If you had used it in your path, then either define the path to maven bin explictly, or change it to something else - like M3_HOME.