Ubuntu – I can’t download new Plasma widgets and Plasma themes in Kubuntu 16.04 LTS

16.04kdekubuntuplasmawidgets

Each time I try to download the new Plasma widget from the Plasma Add-On Installer, I get the following error:

Loading of providers from file: http://download.kde.org/ocs/providers.xml failed

Screenshot:

The same problem is also happening when I am trying to install new theme. Please check the below screenshot for clarification:

Any suggestions, comments or answers will always be appreciated. Thanks.

I found about 20 files in /etc/xdg/ that all reference

ProvidersUrl=http://download.kde.org/ocs/providers.xml

I think the download.kde server currently sends a redirect to

https://autoconfig.kde.org/ocs/providers.xml

But I guess its not followed.

There is a workaround to avoid this problems: "disable the splash screen (System Settings -> Workspace Theme -> Splash Screen -> Set Theme to "None")" (see https://bugs.launchpad.net/ubuntu/+source/breeze/+bug/1584604/comments/14). The bug seems to caused by breeze.

Add Kubuntu Backports repo:

sudo add-apt-repository ppa:kubuntu-ppa/backports

Get key for Neon package archive:

wget -q -O - http://archive.neon.kde.org/public.key | sudo apt-key add -

Add repo:

sudo /usr/bin/add-apt-repository -y -u 'deb http://archive.neon.kde.org/release xenial main'

Install new packages:
```
sudo apt update && sudo apt dist-upgrade
```
4a. You might encounter this problem so follow the workaround provided in the article.

Solution inspired by this thread.