flashcache_load: 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 Debian possible default full paths are:

/sbin/flashcache_load - from package: flashcache-utils

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

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