The wubi installer that comes with Ubuntu 12.04 doesn't allow one to
install ubuntu within windows. I downloaded the Wubi installer available
here Ubuntu Windows Installer
There is absolutely no reason to mount the CD image. Wubi.exe - when run from a CD (or mounted CD image) - no longer supports the 'Install inside Windows' option. Unless you supply
There is absolutely no reason to mount the CD image. Wubi.exe - when run from a CD (or mounted CD image) - no longer supports the 'Install inside Windows' option. Unless you supply
--force-wubi
as a command line option. All you need to do is place wubi.exe in the
same folder as the desktop CD ISO before running wubi. If it starts to
download a new ISO then there is something wrong with your one - check
the log file for details (in the %TEMP% folder, called wubi-12.04-revxxx.log 
