e2fsck: 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:

/sbin/e2fsck - from package: e2fsprogs

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

On Debian possible default full paths are:

/sbin/e2fsck - from package: e2fsprogs
/usr/lib/debug/sbin/e2fsck - from package: e2fsprogs-dbg

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

Error in other languages:
e2fsck: bevel nie gevind nie
e2fsck: comandă negăsită
e2fsck: comando não encontrado
e2fsck: commande introuvable
e2fsck: command not found
e2fsck: käsku ei ole
e2fsck: không tìm thấy lệnh
e2fsck: komanda nerasta
e2fsck: Kommando nicht gefunden.
e2fsck: kommandot finns inte
e2fsck: komut yok
e2fsck: nie znaleziono polecenia
e2fsck: níor aimsíodh an t-ordú
e2fsck: no se encontró la orden
e2fsck: no s'ha trobat l'ordre
e2fsck: opdracht niet gevonden
e2fsck: parancs nem található
e2fsck: perintah tidak ditemukan
e2fsck: príkaz nenájdený
e2fsck: příkaz nenalezen
e2fsck: команда не найдена
e2fsck: командата не е открита
e2fsck: 命令找不到
e2fsck: コマンドが見つかりません