I just spent 30 minutes on this, so I'll provide a much more detailed answer than the above...
1) Open "My Computer"
2) Right Click "This PC"
3) Select "Properties"
4) Select "Advanced System Settings"
5) Select "Environment Variables"
6) Under "System Variables", highlight "Path" row
7) Select "Edit"
8) Select "Browse"
9) Navigate to Anaconda Path (Python should be there; check for python.exe at that location)
10) Restart your cmd.exe; everything should work.