Why I cannot install Bit-locker in my HP TabletPC. Can I install BitLocker in a TabletPC that Comes with ultimate .64 bits. I do not have TPM in my TabletPC. Can I still install BitLocker?

You don't necessarily need TPM so long as you have a USB stick drive which can be used to store the bitlocker code. Check out the instruction for enabling bitlocker on my website to see if they work for you: vistasupport.mvps.org/enable_bitlocker_encryption.htm
John Barnett MVP Associate Expert Windows - Shell/User
Web: xphelpandsupport.mvps.org Web: vistasupport.mvps.org
The information in this mail/post is supplied "as is". No warranty of any kind, either expressed or implied, is made in relation to the accuracy, reliability or content of this mail/post. The Author shall not be liable for any direct, indirect, incidental or consequential damages arising out of the use of, or inability to use, information or opinions expressed in this mail/post..
"Eugene Pinero"

John:
Thank you! I will try it.
Cheers,
Gene
"John Barnett MVP"

John:
I forgot to ask you the following: I have a PNY 4GB 2.0 USB drive that I am using for Ready Boost. Can I use that drive for BitLocker Key too? With anticipated gratitude,
Chees,
Gene
"Eugene Pinero"

Good question. To be honest I'm not entirely sure, simply because I have never tried it. The problem is that bitlocker is there for security reasons and, to be honest, you wouldn't really be wanting such an important piece of information stored on something you are using to 'allegedly increase performance. When i have used bitlocker I have used a 256MB USB drive and, as these are reasonably inexpensive, I would suggest you do the same thing. The USB drive has to be inserted during boot up and then removed prior to Vista reaching the desktop - you are prompted to remove the USB drive.
In the case of ready boost it would really depend upon how much space you have allocated on the USB drive for ready boost to use. Something else you do have to look at is what happens if the drive you are using for ready boost becomes corrupted? You can't get into your system. Having a single USB drive solely for the purpose of bitlocker is a much safer bet.
John Barnett MVP Associate Expert Windows - Shell/User
Web: xphelpandsupport.mvps.org Web: vistasupport.mvps.org
The information in this mail/post is supplied "as is". No warranty of any kind, either expressed or implied, is made in relation to the accuracy, reliability or content of this mail/post. The Author shall not be liable for any direct, indirect, incidental or consequential damages arising out of the use of, or inability to use, information or opinions expressed in this mail/post..
"Eugene Pinero"

John:
Thanks! I will proceed accordingly!
Cheers,
Gene
"John Barnett MVP"