Comment 45 for bug 651678

This error shows up because icons for files recently opened are missing. A fix is to copy/link the missing mimetype icon from /usr/share/icons/gnome/*/mimetypes to /usr/share/icons/oxygen/*/mimetypes (or the icon theme you use). For Anjuta, it is gnome-mime-application-x-anjuta. The * means the sizes that the icon is available: you need to copy/link the icon from one size to the other. To find the files that needs to be linked, run this in terminalfind /usr/share/icons/gnome/* | grep gnome-mime-application-x-anjuta
replace gnome-mime-application-x-anjuta with the one you need.