blastdbcheck: 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/blastdbcheck - from package: ncbi-blast+

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

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