Install kde4pimlibs-kio-plugins by entering the following commands in the terminal:
sudo apt update sudo apt install kde4pimlibs-kio-plugins
Description:
kio slaves used by KDE PIM applications
This package contains the imap4, ldap, mbox, nntp, pop3, sieve and smtp kio slaves. . This package is part of the KDE Development Platform PIM libraries module.
Homepage: http://pim.kde.org/
Version: 4:4.14.10-1ubuntu7
Section: universe/libs