You may have to leave 'knoppix' as the default user for running from CD, there are a lot of references in the startup configuration scripts that depend on the user being 'knoppix'.
You can change the username once you install to a HD.
Im working in my own remastered version from knoppix 3.4
... The next step it change the user from knoppix to another... Delte the knoppix user and create another one.
Where i have to put my hands to do this???...
I need some orientation....
Any Clue?
You may have to leave 'knoppix' as the default user for running from CD, there are a lot of references in the startup configuration scripts that depend on the user being 'knoppix'.
You can change the username once you install to a HD.
Clearly, since he said he's remastering, he could change the user name. I'm miles away from being able to remaster, so I'm not even going to pretend I know how to make that change, but it certainly can be change and shoud be straight forward.
The knoppix name is set in the knoppix startup scripts. You can edit them if you remaster. Be sure to look into the initrd, there is a file linuxrc. Next, look at the files in /etc/init.d/knoppix-... and /etc/init.d/xsession - then you should be able to change the user name.
Earlier, I suggested a user= cheatcode. It would be a very nice feature for some.

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