config: 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/lib64/R/bin/config - from package: R-core
/usr/lib/R/bin/config - from package: R-core

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

On Debian possible default full paths are:

/usr/lib/R/bin/config - from package: r-base-core

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

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