storeBackupVersions: 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
/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/storeBackupVersions - from package: storebackup
/usr/share/storebackup/bin/storeBackupVersions - from package: storebackup

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