chktrust: 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 CentOS possible default full paths are:

/usr/bin/chktrust - from package: mono-core

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

On Debian possible default full paths are:

/usr/bin/chktrust - from package: mono-devel

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