Command not recognised

I'm having issues with commands for editing source files. If I use the command "edit" or "notepad" the error message will appear saying "'edit/notepad' is not recognised as an internal or external command, operable program or batch file". How am I to solve this problem?

I have a screenshot of this that I can e-mail if anyone would like to see it for themselves, any help would be appreciated.

Welcome
A screen shot would be very helpful. No need to use email, you can upload here so all members may offer help.
http://www.vistax64.com/tutorials/289032-screenshots-files-upload-post-vista-forums.html