size86: 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/size86 - from package: dev86

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

On Debian possible default full paths are:

/usr/bin/size86 - from package: bin86

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

Error in other languages:
size86: bevel nie gevind nie
size86: comandă negăsită
size86: comando não encontrado
size86: commande introuvable
size86: command not found
size86: käsku ei ole
size86: không tìm thấy lệnh
size86: komanda nerasta
size86: Kommando nicht gefunden.
size86: kommandot finns inte
size86: komut yok
size86: nie znaleziono polecenia
size86: níor aimsíodh an t-ordú
size86: no se encontró la orden
size86: no s'ha trobat l'ordre
size86: opdracht niet gevonden
size86: parancs nem található
size86: perintah tidak ditemukan
size86: príkaz nenájdený
size86: příkaz nenalezen
size86: команда не найдена
size86: командата не е открита
size86: 命令找不到
size86: コマンドが見つかりません