track_info: 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/mrtrix/bin/track_info - from package: mrtrix

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

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