ecaccess-certificate-list: 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/ecaccess-certificate-list - from package: ecaccess

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

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