How To Change The Password On "Password Protected File Sharing"

So I've enabled password protected sharing for Windows 7 (for my first computer).



So now, when I used my second computer to access my first computer's shared files, it obviously prompted me with a password.

My question is, I don't know what's the username and password for that. I was wondering if someone can help me to find my username and password (or guide to reset this password) so my second computer can access the shared files with my first computer while preserving the password security.

Use the username and password that you use when you log onto the first computer.

If that does not work, try
user = computername\user
password = password

...where computername = the name of the first computer.