synaptic missing authentication tab

[klaus2008]

I started synaptic package management and reloaded the package information. Then I installed the package software-properties-gtk and its dependencies. In the 'Settings' menu I selected 'Repositories' and got a dialog window with five tabs. One tab is called 'Authentication' and allows you to import a key file.

[dunnthebum]

I started synaptic package management and reloaded the package information. Then I installed the package software-properties-gtk and its dependencies. In the 'Settings' menu I selected 'Repositories' and got a dialog window with five tabs. One tab is called 'Authentication' and allows you to import a key file.

Did that and it works. Thanks.
Why is this not included by default in the knoppix cd?