copymat: command not found

Have You tried accessing the binary with the full path?

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/copymat - from package: blast2

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