sivtest: 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/sivtest - from package: cyrus-imapd-utils

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

On Debian possible default full paths are:

/usr/bin/sivtest - from package: cyrus-clients

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

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