murmur-user-wrapper: 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/murmur-user-wrapper - from package: mumble-server

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

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