dcmmkcrv: 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/dcmmkcrv - from package: dcmtk

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

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