dmtxquery: 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/dmtxquery - from package: libdmtx-utils

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

On Debian possible default full paths are:

/usr/bin/dmtxquery - from package: dmtx-utils

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

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