Ok. Still not getting anywhere. I don't use command prompt very often so if I'm missing something obvious, please spell it out.
Microsoft Windows [Version 6.1.7601] Copyright © 2009 Microsoft Corporation. All rights reserved. C:\Users\Will Vallance> C:\Users\Will Vallance>ftype jarfile="C:\Program Files\Java\jre7\bin\javaw.exe" -jar "%1" %* File type 'jarfile' not found or no open command associated with it. C:\Users\Will Vallance>