otrs.ExecuteDatabaseXML.pl: 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/share/otrs/bin/otrs.ExecuteDatabaseXML.pl - from package: otrs2

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

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