phpcb: 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/phpcb - from package: php-phpunit-PHP-CodeBrowser

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

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