kill-avarice: 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/kill-avarice - from package: avarice

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

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