uncompress.real: 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/uncompress.real - from package: ncompress

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

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