pgmtexture: 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/pgmtexture - from package: netpbm-progs

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

On Debian possible default full paths are:

/usr/bin/pgmtexture - from package: netpbm

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

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