Do you know for sure that your kernel sources are installed?
There are scripts from kanotix http://kanotix.com/files/ for installing
kernel sources.
You could also check to make sure your path is showing the kernel sources.
Does anyone else get this in knoppix? (after having installed to harddrive). When you go into the configuration utility, and select "System Administration" -> "Linux kernel" it says "Sorry, The kernel configurator could not be read due to the following error: No hardware architecture was specified! Perhaps the kernel source code is not installed on this system, or the path to the kernel sources is entered incorrectly. Either your kernel sources contain invalid configuration rules or you just found a bug in KDE"
I've gotten this every time i've installed knoppix. The first time i thought i had just screwed something up again, but this is a fresh install of knoppix 3.7 on a Dell Inspiron 8000.
Should i recompile my kernel?
Do you know for sure that your kernel sources are installed?
There are scripts from kanotix http://kanotix.com/files/ for installing
kernel sources.
You could also check to make sure your path is showing the kernel sources.
AFAIK kanotix kernel no longer work with knoppix so the source is also different. Try http://developer.linuxtag.org/knoppix/
Even with that, I don't think you can use K-menu for it so best just to compile manually for example with make menuconfig

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