start-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/start-avarice - from package: avarice

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

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