I am using Linux Mint 14 XFCE.  I am trying to remove the default XFCE window manager shortcuts for workspace switching (Ctrl-F1, Ctrl-F2, etc.), as described in this question.The answers there don't have any effect for me.  If I go into Settings->Window Manger->Keyboard, nothing I do has any effect.  If I click on a setting and hit Clear, the setting stays there unchanged.  If I double-click on a setting and choose a new shortcut key, the original settings stays there unchanged.  If I go into Settings Editor (as described in the other answer to that question) and attempt to reset the settings there, nothing has any effect still.What is going on?  How can I get XFCE to let me change the keyboard shortcut settings?
Cannot change global keyboard shortcuts in Linux Mint XFCE
linux mint;keyboard shortcuts;xfce;window manager