ftvalid: 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/ftvalid - from package: freetype-demos

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

On Debian possible default full paths are:

/usr/bin/ftvalid - from package: freetype2-demos

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

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