owncloudcmd: 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/owncloudcmd - from package: owncloud-client-cmd

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

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