nsopenssl.so: 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/lib/aolserver4/bin/nsopenssl.so - from package: aolserver4-nsopenssl

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