blastpgp: 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/blastpgp - from package: blast2
/usr/share/ncbi-blast+/bin/blastpgp - from package: ncbi-blast+-legacy

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

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