I BUY 2 replacement 40GB and 60gb HDD and they are Hitachi, just like the 40gig one I pulled out.
I run 4 recovery CDs and they include all preloaded software, drivers and a copy of Windows XP. I booted to the CD and followed the instructions through all 4 CDs. At the end of the 4th CD it says: "Recovery Continuing, Remove any diskettes or CDs from the drives, and press Enter to restert your computer." When I do that, all I get is a blank screen with a flashing cursor in the upper left corner.
i put the other hdd in,I've run the CDs same result again. I've ordered another set of CDs thinking they were missing something, same result.
During the CD load, I can see the HDD light blinking indicating action on the new drive. When I look at the BIOS, it recognizes the new HDD because it list it by model number. I've changed the BIOS security settings for the IBM Predesktop Area to DISABLE as recommended by someone on another board, same result.
my question is why the original hdd boots up with no problem but not the other 2 hdds i tried. all of these 3 hdds are healthy and boot up on other laptops but on this particular r40 only the original one boot up not the others and it must not be related to capacity cuz the other 2 hdds are 40gig and 60gig and presume to work.
so can some1 gimme an idea whats wrong?

Assuming the recovery CD set is specific to that series of thinkpad models, from memory what is supposed to occur when it asks to restart, is the recovery process will run a really huge "command" file from a DOS window within whichever version of windows it is trying to configure with all the correct drivers and utilities for that R40..

i can't say where it is failing but the first thing i would try is a hard reboot..
if you have not already tried that..

The problem is the Initialization of the HD.
Get DBAN from http://www.dban.org, burn the CD or make a USB stick, and run that for ca. 5% of the HD, that's enough.
This will wipe the MBR and partition table and some other sectors (made by the previous HD user), which for some strange reason are different from an IBM-made one.
Now reboot again with your first R&R CD, and make sure it partitions/formats the HD first, before installing.

can't we init it in a simple way?
by the way i cloned the original drive over the other ones with norton ghost.
i suppose it must overwrite MBR and partition table too, so still its a mystery to me why the machine stuck at such step with a blinking cursor and wont continue to boot.
is there a way to only copy and overwrite the initialization blocks from the original drive to these new drives and solve this strange problem?

i also have suspicion i discuss here, as u all know this model wont accept a wifi card and rejects it with an authorization error number cuz the ibm locked this machine bios to accept only a particular type of wifi card.
so, it seems logical to me if ibm also locked the bios/controller to only accept a particular kind of harddisks.
any thought on that?

Nope. Never happened.

Even on T43/R52/X41 where you get the "2010 error" you can still boot from a non-whitelisted disk.

Having owned more R40 units than I dare remember, I will state that there is NO limitation of any kind on these machines when it comes to hard drives.

How you clone is very important, it should be from the original drive in e.g. an external case onto the new drive inside the R40 drivebay.
Any other way gives the error you have.

i also done retried as u said about cloning procedure, no success.
i used FIXMBR and FIXBOOT commands from XP RECOVERY CONSOLE installation boot disk and no success.
but i used an option from hiren`s bootcd dos startup menu called BOOT XP FROM HDD, and my cloned hdd starts boot up the xp on it fast, i`m gonna stick to this methode for now,
cuz i use my r40 as a overnight download station running on ac wall outlet power and its stays on almost all the times, so not a big hassle for me to boot this machine from cd instaed of its hdd every now and then.
however with my 10 years technical experience with maintenance/repair of desktops/laptops its still a mystery why i confront this problem, i even solved the whitelist/blacklist wifi card problem of this machine via debug command and installed a 3rd party wifi card inside, but this problem not solved yet! very odd and challenging!
i know some utils dedicated only to backup/restore mbr/bootsectors and i think maybe they can help me to fix this booting issue, dont u think so?

You need to enable the pre-desktop area to begin with...that's where the restore partition gets stored during the install from the recovery disks...

but i want to install my own xp from a retail cd. how about that.

Back to my first post: use DBAN and wipe the first 5% of the HD.
Then let your retail CD partition/format the HD and install XP.
IBM (used to) have a different MBR from anyone else.