docx2txt: command not found

Have You tried accessing the binary with the full path?

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/docx2txt - from package: docx2txt

You may install the required package with command apt-get install {package}
Error in other languages:
docx2txt: bevel nie gevind nie
docx2txt: comandă negăsită
docx2txt: comando não encontrado
docx2txt: commande introuvable
docx2txt: command not found
docx2txt: käsku ei ole
docx2txt: không tìm thấy lệnh
docx2txt: komanda nerasta
docx2txt: Kommando nicht gefunden.
docx2txt: kommandot finns inte
docx2txt: komut yok
docx2txt: nie znaleziono polecenia
docx2txt: níor aimsíodh an t-ordú
docx2txt: no se encontró la orden
docx2txt: no s'ha trobat l'ordre
docx2txt: opdracht niet gevonden
docx2txt: parancs nem található
docx2txt: perintah tidak ditemukan
docx2txt: príkaz nenájdený
docx2txt: příkaz nenalezen
docx2txt: команда не найдена
docx2txt: командата не е открита
docx2txt: 命令找不到
docx2txt: コマンドが見つかりません