vbthresh: 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/lib/voxbo/bin/vbthresh - from package: voxbo

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

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