Hi Derick,

I see you have had a good sleep.

Sorry but occasionally we get someone who creates a thread just to rant. They are usually ignored because no one expects them to hang around long enough to read a response. Seems you do still want to know so I'll try.

Debian has its own package management system and so do all Debian based distributions of which Knoppix is just one. There are many. The biggest is the Big Brown distribution whose recent releases have names like Manky Manatee, Lazy Lizard and Karaoke Kookaburra.

The package management back-end is named apt. It has a command line interface. There are GUI front-ends: synaptic is one. I expect the good folks over at the Big Brown distribution have 'improved' synaptic (aka made is more user friendly). As a user friendly GUI front-end it makes assumptions so you don't have to.

Nice as GUIs are, if, by chance, you do make an assumption and your assumption is wrong you are probably in for some serious sleep deprivation. Remember, when it comes down to it, you, not the software, are going to blink first. No matter what you believe, the software is not going to back down, admit that it is wrong and start behaving the way you expect it to.

There is a directory /etc/apt under which you will find all the configuration files used by apt. The Software Centre app you had so much trouble with is a python script that presents some of this configuration in a series of tabs to give you feeling you are in control.

The first tab will identify your principle repository. For users of the Big Brown distribution this will confirm they actually have installed the version they thought they had installed. Nice. The second tab would show any additional repositories the user has added to their configuration.

There is a snag. The list of repositories is in (to keep the description simple) the file /etc/apt/sources.list. It is just a list. There is no concept of principle repository in apt. I guess that somehow the sources list used in Big Brown distributions has some kind of marker in a comment to indicate the principle repository.

Without that marker what happens ?

If, in your Knoppix, you compare the second tab with the file, you'll find they cover the same repositories. Unchecking a repository in the GUI app simply comments out the corresponding line in the file (you have to save your changes to see this),

There is no principle repository marked in the /etc/apt/sources.list. You and I might expect therefore the first tab in the GUI app would be absent but the GUI app does not know this. You can't check or uncheck the boxes on the first tab because there are no lines to comment or uncomment in /etc/apt/source.list. Dumb I know, but, hey, that's user friendly for you.

Why has no one else noticed ? Perhaps because /etc/apt/sources.list has all anyone needs already (enabled). Perhaps because to change the repositories from the default German ones to something a little closer to home is not the kind of user friendly thing you can do in the GUI app so folks are used to editing the file directly. Perhaps because most people try synaptic first and, once they've learnt how to refresh the package lists (I think that's the reload button) they get what they want so they look no further. Perhaps because some of them, like me, use the command line apt.

It's a stupid bug. It's not a Knoppix bug. Sorry you wasted so much time on it.