texexpand: 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/texexpand - from package: latex2html

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

On Debian possible default full paths are:

/usr/bin/texexpand - from package: latex2html

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

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