Windows can't read the data on newly connected HDD but testdisk can both show them and recover them

Question

I gave a friend of mine my internal 1.5TB HDD to copy alot of files for me. When he gave it back to me i tried reattaching it to my desktop but Windows couldn't read the HDD or recognize it, so i tried using testdisk to recover my MFT table but even though it managed to write the MFT table and i actually managed to browse through the files and recover some of the data, Windows still couldn't recognize the HDD (Even after making the partition active and giving it a new letter).

This is what the Disk Management on Windows shows me:

And it does not allow me to change the drive's letter, so the drive is not showing when opening "My Computer" or listing the drives.

I tried using one of the commercial softwares out there named Aoemi Partition Assistant But it went as far as showing me this:

I tried to rebuild MBR and then convert the Disk to MBR, but the used size would dramatically change to 450 MBs ! And when trying to use that same software to change the drive's letter, it fails with an unknown error and asks me to use the Windows Drive Management to change the drive's letter which is not doable!

I am currently clueless on what to do, as i've been going in loops for 3 days now, and i am really afraid i'd damage it (i am hoping i haven't done that already, since i can still recover some of the data using testdisk).

Thanks,

Extra information: I am using a 32bit Windows XP Desktop pc.

Answer 1

the clue is in your second picture - the disk is a GPT Protective Partition. This means the data has been accessed on a system that does not properly understand GPT disks. The only Windows systems that understand GPT disks are XP (64 Biit only), Vista, Windows 7 and Windows 8

The only way I have seen to retrieve the data without cost is to boot using a linux live CD, and shrink the partition as much as is allowed, and create a new partition.
Copy as much data as you can, and repeat the cycle until you have all the data.

the cost method: (currently $36) http://www.extend-partition.com/help/convert-gpt-mbr-disk.html

alternatively: (you will lose your data)
diskpart
select disk X where X is your drive
clean - but this will set the whole disk as unallocated, and you will lose your data

Answer 2

In the image you supplied the disk shows up as 1.4TB, which is about 1.5TB after marketing has rounded the value.

The red arrows on same image shows the used space. This is how much files are on the disk. (not how much of the disk is used).

All in all I see nothing wrong. It is a working 1.5TB disk. It was partitioned using GPT which is a newer standard. I can understand that a 12-ish year old OS (XP) has a problem with that. But you already got it working. Is there any problem at all if you just 'open' the disk and access the files on it?