Disable automated updates (and notifications) in Kde Debian

I am using Kde 4.5 in Debian and I get some notifications after start that I need to update something. How can I disable it (I often don't want to waste bandwidth for such things)?

I am using Debian Wheezy and Kde 4.5

Open the KDE System Settings application. (I find the easiest way is to press Alt+F2, type in systemsettings, and press Enter. But you can also launch it from the K menu if you like.)

Choose Software Management under System Administration:

Then select Settings from the left panel, and under Check for updates, choose Never:

Finally, click Apply. KPackageKit will no longer bother you about updates. But, remember to use apt-get or your favorite package manager to download updates periodically so you aren't exposed to security vulnerabilities.

This question was originally asked and answered for KDE 4.5. As of 2021, KDE Plasma 5 is most commonly used, so this answer addresses how to disable automatic updates and automatic update checks in KDE Plasma 5.

On most systems running KDE Plasma 5, there is an application called Discover. This application is partially responsible for automatic updates and contains the settings for configuring automatic updates.

In order to disable automatic updates or automatic update checks:

1. Open Discover. You can do this by pressing Alt+F2 and typing Discover or by searching for Discover in your Application Launcher.

2. In the bottom, left corner of the Discover window, there is a button called Settings you can use to open Discover's settings.
   Discover window with location of Settings button indicated

3. In Discover's settings view, you will see a button in the top, right corner labeled Software Sources. This button will open Discover's software sources and settings window.
   Discover window with location of Software Settings button indicated

4. Once you have entered your administrator password, Discover's software sources and settings window will open. This window has a tab called Updates.
   Software Sources window with Updates tab indicated

5. Under the Updates tab, you will find a section titled Automatic updates. This section contains settings for update checks and automatic installation. Here you can disable automatic update installation by selecting the option: Only notify about available updates. You can disable automatic update checks entirely by unchecking the checkbox: Check for updates.
   Updates tab with automatic update installation disabled
   Updates tab with automatic update checks disabled

This process has been tested on Kubuntu 20.04 LTS but should work on other KDE Plasma 5 based systems as well.