You need to give us more detail. Are you running the live CD in a vm or have you installed to a virtual hd? Also can you post the error messages you see when you attempt to save the file?
i already installed it..
no particular error..but on vi editor to save i used ":wq","ZZ"..
but nothing is working..
When you issue the :w command you should see something like
at the bottom of the vi terminal. What is displayed in yours?Code:"test.sh" 2L, 25C written 2,1 All
Also, what version of Knoppix did you install and have you tried a different editor?

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