chkweb: 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/chkweb - from package: chktex

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

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