By default when CentOS is installed not all the gnome utils are loaded in the system.
The screenshot utils is one of them that is not loaded.
So trying to take a screenshot would fail:

ERROR:

There was an error running gnome-screenshot: Failed to execute child process “gnome-screenshot”

Only the utilities below were available:

  • gnome-about
  • gnome-about-me
  • gnome-appearance-properties
  • gnome-at-properties
  • gnome-at-visual
  • gnome-audio-profiles-properties
  • gnome-character-map
  • gnome-control-center
  • gnome-default-applications-properties
  • gnome-desktop-item-edit
  • gnome-display-properties
  • gnome-font-viewer
  • gnome-help
  • gnome-keybinding-properties
  • gnome-keyboard-properties
  • gnome-keyring
  • gnome-keyring-daemon
  • gnome-mouse-properties
  • gnome-network-properties
  • gnome-open
  • gnome-panel
  • gnome-power-bugreport.sh
  • gnome-power-manager
  • gnome-power-preferences
  • gnome-screensaver
  • gnome-screensaver-command
  • gnome-screensaver-preferences
  • gnome-session
  • gnome-session-properties
  • gnome-session-save
  • gnome-terminal
  • gnome-text-editor
  • gnome-thumbnail-font
  • gnome-typing-monitor
  • gnomevfs-cat
  • gnomevfs-copy
  • gnomevfs-df
  • gnomevfs-info
  • gnomevfs-ls
  • gnomevfs-mkdir
  • gnomevfs-monitor
  • gnomevfs-mv
  • gnomevfs-rm
  • gnome-volume-control
  • gnome-volume-control-applet
  • gnome-wacom-properties
  • gnome-window-properties
  • gnome-wm

As you can see, gnome-screenshot wasn’t there.

To install the gnome-screenshot util:

[sourcecode language=”bash”]
sudo yum install gnome-utils
[/sourcecode]

That should fix the problem and you should be able to take screenshots as you would normally expect:

The official webpage for the gnome-utils project