orderchr.0: 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/circos/tools/orderchr/bin/orderchr.0 - from package: circos-tools

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

Error in other languages:
orderchr.0: bevel nie gevind nie
orderchr.0: comandă negăsită
orderchr.0: comando não encontrado
orderchr.0: commande introuvable
orderchr.0: command not found
orderchr.0: käsku ei ole
orderchr.0: không tìm thấy lệnh
orderchr.0: komanda nerasta
orderchr.0: Kommando nicht gefunden.
orderchr.0: kommandot finns inte
orderchr.0: komut yok
orderchr.0: nie znaleziono polecenia
orderchr.0: níor aimsíodh an t-ordú
orderchr.0: no se encontró la orden
orderchr.0: no s'ha trobat l'ordre
orderchr.0: opdracht niet gevonden
orderchr.0: parancs nem található
orderchr.0: perintah tidak ditemukan
orderchr.0: príkaz nenájdený
orderchr.0: příkaz nenalezen
orderchr.0: команда не найдена
orderchr.0: командата не е открита
orderchr.0: 命令找不到
orderchr.0: コマンドが見つかりません