soapdenovo2-63mer: command not found

Have You tried accessing the binary with the full path?

Maybe Your $PATH variable doesn't contain the default paths? echo $PATH should give something like:

[root@server ~]# echo $PATH

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/soapdenovo2-63mer - from package: soapdenovo2

You may install the required package with command apt-get install {package}
Error in other languages:
soapdenovo2-63mer: bevel nie gevind nie
soapdenovo2-63mer: comandă negăsită
soapdenovo2-63mer: comando não encontrado
soapdenovo2-63mer: commande introuvable
soapdenovo2-63mer: command not found
soapdenovo2-63mer: käsku ei ole
soapdenovo2-63mer: không tìm thấy lệnh
soapdenovo2-63mer: komanda nerasta
soapdenovo2-63mer: Kommando nicht gefunden.
soapdenovo2-63mer: kommandot finns inte
soapdenovo2-63mer: komut yok
soapdenovo2-63mer: nie znaleziono polecenia
soapdenovo2-63mer: níor aimsíodh an t-ordú
soapdenovo2-63mer: no se encontró la orden
soapdenovo2-63mer: no s'ha trobat l'ordre
soapdenovo2-63mer: opdracht niet gevonden
soapdenovo2-63mer: parancs nem található
soapdenovo2-63mer: perintah tidak ditemukan
soapdenovo2-63mer: príkaz nenájdený
soapdenovo2-63mer: příkaz nenalezen
soapdenovo2-63mer: команда не найдена
soapdenovo2-63mer: командата не е открита
soapdenovo2-63mer: 命令找不到
soapdenovo2-63mer: コマンドが見つかりません