jmtpfs: 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 CentOS possible default full paths are:

/usr/bin/jmtpfs - from package: jmtpfs

You may install the required package with command yum install {package}

On Debian possible default full paths are:

/usr/bin/jmtpfs - from package: jmtpfs

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

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