ireminder: 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 Debian possible default full paths are:

/usr/bin/ireminder - from package: itools

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

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