scheme-script: 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/scheme-script - from package: ikarus

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

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