roxterm: 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 CentOS possible default full paths are:

/usr/bin/roxterm - from package: roxterm

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

On Debian possible default full paths are:

/usr/bin/roxterm - from package: roxterm-gtk2
/usr/bin/roxterm - from package: roxterm-gtk3

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

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