anytopnm: 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/anytopnm - from package: netpbm-progs

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

On Debian possible default full paths are:

/usr/bin/anytopnm - from package: netpbm

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

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