I've lost myadmin account password on my PC and only have got this guest account can anybody help me its really urgent.

Oh really? So you're an admin? Or was the name of your account "myadmin"? If you really did lose your "admin account" (which I highly doubt you had), PM any S-Mod (user with a blue name), and explain the situation to them.

lol think about your name maybe somebody hacked it

I believe he means his actual computers Administration account, not Toribash. I'll see if I can figure anything out, Cropandur.

Ohhh. That makes a whole lot more sense now..
If you have any other admin accounts on your computer, this can be reversed. (By resetting the password.) Otherwise, you're going to need some hardware to retrieve the password safely without damaging any of your files.

What OS are we talking about here?

Hahaha I remember being in a similar boat (although it was probably less moral xD)

assuming you are using windows (you said PC which is generally associated with windows OSДs)
There are programs you can install on a USB drive to override the login.
quick google seacrh got me this
http://www.raymond.cc/blog/archives/...ging-password/
I believe there are similar programs if you are on win7

or you can decrypt the password using Јrainbow hash tablesЈ which is what I did, but it takes alot longer...