fts-set-priority: 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/fts-set-priority - from package: fts-client

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

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