malshow: 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/malshow - from package: malaga

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

On Debian possible default full paths are:

/usr/bin/malshow - from package: malaga-bin

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

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