dspam_crc: 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/dspam_crc - from package: dspam

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

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