|"there is a password on the hdd that I put there a few year ago I dont rember it "|
We've been told similar to that frequently.
We suspect that the vast majority of the situations where someone has an unknown password - a hard drive access password or a system access password - that was set in the bios of a laptop or netbook, the computer was stolen, or the hard drive was stolen, or the person asking is trying to access someone else's computer they should not have the right to access.
It's extremely unlikely you would forget a password you had to use every time you used the computer - a hard drive access password or a system access password - unless you have serious memory problems.
It's certainly possible for a legitimate owner of a laptop or netbook to forget a bios access password that was set in the bios if they rarely used it, but that's usually a problem you can get around, if all you want to be able to do is boot the computer from a different device. In most if not all cases you see a line while booting that states "Press (a key) to select boot device" or similar - you press that key while that line is on the screen and select the device you want to boot the computer from.