kdm refuses to let me log in

Reason: PAM problems (RedHat systems) Red Hat has released a PAM security update. Download a new RPM matching your distribution's version from RH's errata.

Most KDE applications crash immediately

Reason:Use of Qt 2.2.1

There was an incompatibility between libpng 1.0.8 or newer and Qt older than version 2.2.2. This caused every application to crash as soon as anything png related was invoked. To fix this, either downgrade libpng to 1.0.7 or (recommended) upgrade Qt to version 2.2.2. See the libpng homepage.

Most KDE applications crash immediately

Reason:Environment variables set incorrectly

The environment variables KDEDIR, KDEHOME, PATH and LD_LIBRARY_PATH, if set, must point to the correct KDE 2.0 locations. RedHat users should make sure to change their kde.csh and kde.sh scripts.

Most KDE applications crash immediately

Reason:Missing ksycoca database

In some installations the KDE program kbuildsycoca fails to properly create a file called ksycoca. This file is needed by KDE to operate properly. Depending on the environment variable $KDEHOME this file should either be found in ~/.kde/share/config/ksycoca or ~/.kde2/share/config/ksycoca.

Make sure that your $KDEHOME environment variable is always set to the same value. Leaving it empty is OK, it will then assume ~/.kde in which case you should have a recent ksycoca in ~/.kde/share/config/ksycoca.

Run kbuildsycoca from a command line to generate the ksycoca file.

DCOPServer fails to start

Reason:Too old version of Qt

You need to have at least Qt version 2.2.1. Version 2.2.0 is NOT sufficient, no matter what your RPM says.

Logout problems

Various people have reported that they are not able to log out from KDE. Others have reported that logging out takes a very long time. No exact reason for this failure is currently known.

Why can't I hear any sound ?

Stefan Westerfeld has compiled a aRts FAQ that will help you going.

Why is Konqueror/khtml unable to display some images on the web?

Reason:You didn't compile Qt to include support for those formats

Make sure that you included support for them while compiling Qt.

for GIF images, include -gif during configuring (if you have a GIF license).
for JPEG images, make sure that you have jpeglib6b installed while configuring kdelibs.
for MNG movies, make sure that you compiled Qt with -system-libmng

Konqueror problems

See the Konqueror FAQ for Frequently Asked Questions and their answers concerning KDEs webbrowser and file-manager.

KMail and KNode frequently crash (Caldera Open Linux 2.4)

Reason:A conflict between the mimelib versions distributed with KDE 1.x and 2.0

Updated RPMS will be made available soon. Temporary workaround:

cd /opt/kde/lib
rm libmimelib.so
ln -s /usr/lib/libmimelib.so.1.0.1  libmimelib.so
rm libmimelib.so.1
ln -s /usr/lib/libmimelib.so.1.0.1  libmimelib.so.1

Logout and other tasks take very long

Reason:Problems resolving your hostname

Upon certain action KDE does a lookup of your hostname. If you rely on DNS for resolving and the network is slow or down this will lead to a immense slowdown.

Fix: add your host with name and IP address to /etc/hosts and make sure that /etc/host.conf contains order hosts,bind (or similar).