'MySQL' is not recognized as an internal or external command, operable program or batch file

In Windows 8 Command Prompt, when I typed heroku, it showed this error message.

Solution?

Simply wrap double quote around the system path

from:

C:\Program Files (x86)\MySQL\MySQL Fabric 1.5.4 & MySQL Utilities 1.5.4 1.5\

to:

"C:\Program Files (x86)\MySQL\MySQL Fabric 1.5.4 & MySQL Utilities 1.5.4 1.5\"

Tips: type sysdm.cpl in command prompt to quickly fire up the system properties window :)