i810rotate: 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:

/usr/bin/i810rotate - from package: i810switch

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

Error in other languages:
i810rotate: bevel nie gevind nie
i810rotate: comandă negăsită
i810rotate: comando não encontrado
i810rotate: commande introuvable
i810rotate: command not found
i810rotate: käsku ei ole
i810rotate: không tìm thấy lệnh
i810rotate: komanda nerasta
i810rotate: Kommando nicht gefunden.
i810rotate: kommandot finns inte
i810rotate: komut yok
i810rotate: nie znaleziono polecenia
i810rotate: níor aimsíodh an t-ordú
i810rotate: no se encontró la orden
i810rotate: no s'ha trobat l'ordre
i810rotate: opdracht niet gevonden
i810rotate: parancs nem található
i810rotate: perintah tidak ditemukan
i810rotate: príkaz nenájdený
i810rotate: příkaz nenalezen
i810rotate: команда не найдена
i810rotate: командата не е открита
i810rotate: 命令找不到
i810rotate: コマンドが見つかりません