xfsettingsd: command not found

Maybe Your $PATH variable doesn't contain the default paths? echo $PATH should give something like:

[root@server ~]# echo $PATH
/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin

If it's empty, You may set the PATH variable with this command

export PATH="/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin"

On CentOS possible default full paths are:

/usr/bin/xfsettingsd - from package: xfce4-settings

You may install the required package with command yum install {package}

On Debian possible default full paths are:

/usr/bin/xfsettingsd - from package: xfce4-settings

You may install the required package with command apt-get install {package}

Error in other languages:
xfsettingsd: bevel nie gevind nie
xfsettingsd: comandă negăsită
xfsettingsd: comando não encontrado
xfsettingsd: commande introuvable
xfsettingsd: command not found
xfsettingsd: käsku ei ole
xfsettingsd: không tìm thấy lệnh
xfsettingsd: komanda nerasta
xfsettingsd: Kommando nicht gefunden.
xfsettingsd: kommandot finns inte
xfsettingsd: komut yok
xfsettingsd: nie znaleziono polecenia
xfsettingsd: níor aimsíodh an t-ordú
xfsettingsd: no se encontró la orden
xfsettingsd: no s'ha trobat l'ordre
xfsettingsd: opdracht niet gevonden
xfsettingsd: parancs nem található
xfsettingsd: perintah tidak ditemukan
xfsettingsd: príkaz nenájdený
xfsettingsd: příkaz nenalezen
xfsettingsd: команда не найдена
xfsettingsd: командата не е открита
xfsettingsd: 命令找不到
xfsettingsd: コマンドが見つかりません