Most modern-day window managers contain desktop managers that create the look and feel of the desktop. Overall, this is referred to as the desktop environment. GNOME originally used the Enlightenment Window Manager, but later revisions moved to the Sawfish Window Manager, whereas the K Desktop Environment uses its own K Window Manager. Essentially, the window manager, as discussed earlier, controls the X server's look and feel, whereas the desktop manager controls the window management.
Troubleshooting the desktop environment can be a daunting task. Each desktop has configuration files stored in the user's home directory. KDE stores users' configuration files under $HOME/.kde, whereas GNOME uses $HOME/.gnome. The best way to troubleshoot the desktop environment is simply to use a new user account to see whether the problem still exists. If the problem does not exist for the new user, then there is something wrong in the configuration files. Divide and conquer. Rename the configuration directory and log back in, and the desktop environment will create a new configuration directory and take the user to default settings. Eventually, you will find the root cause.