How to add password to internal hard drive?

Hello fellow Windows 7 users,
I have a WD Caviar Green 2tb desktop hard drive that I bought to backup all my files on using a SATA to USB converter cable to connect it to my laptop (the hard drive cost me $40, quite a bit cheaper than buying another My Passport 2tb). I would like to add a password to it like I did to my My Passport external hard drive, where it requires a password to access the content on the drive. I called WD and they said that I couldn't. Of course there must be some sort of 3rd party software out there.
Thanks

Encryption is pretty much your only option.
A password works on your external drive because it is part of the firmware of the drive and cannot be bypassed by normal methods. Your internal drive lacks this feature. The basic principle (pretty much universal) is that security is not an add-on. It is something that must be designed in.

Encryption works because the security is in the data itself, not the device that contains it.

NTFS security isn't much good here either. Attach the drive to a computer on which they have admin rights and anyone can set whatever permissions they wish.

LMiller7 said:

Encryption is pretty much your only option.
A password works on your external drive because it is part of the firmware of the drive and cannot be bypassed by normal methods. Your internal drive lacks this feature. The basic principle (pretty much universal) is that security is not an add-on. It is something that must be designed in.

Encryption works because the security is in the data itself, not the device that contains it.

NTFS security isn't much good here either. Attach the drive to a computer on which they have admin rights and anyone can set whatever permissions they wish.

so its not possible unless i "encrypt" it? I have no idea how to encrypt it so how would i do this and how does it work?

whs said:

Yes if you have Windows Pro or Ultimate

Yeah i upgraded to ultimate a while back.