I found out what the problem was, i was entering an old password, so the problem was incorrect password. I would delete this post but I don't know how. Derp xD
I bought a new gaming keyboard for my very old computer (10 years+). The model of gaming keyboard is "Scorpion K632" and when I enter my password for "TrueCrypt" encryption, it says incorrect password.
(Yes i know I need to use "Bitlocker" instead, because of the security flaws in Truecrypt)...