psl: 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/psl - from package: psl

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

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