nph-genericinterface.pl: 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 Debian possible default full paths are:

/usr/share/otrs/bin/cgi-bin/nph-genericinterface.pl - from package: otrs2
/usr/share/otrs/bin/fcgi-bin/nph-genericinterface.pl - from package: otrs2

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