comtest: 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/comtest - from package: ivtools-bin

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

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