dcmcjpeg: 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/dcmcjpeg - from package: dcmtk

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