the newly connected drive reads GTP protected partition
(if this is at all relevant ). I am using Win XP.
Yes, this is the key to the problem.
Techpumpkin already provided a very short but correct answer.
Let me try to expand a little bit on it as to why this is so.
A disk can be used RAW, or it can be partitioned. Different operating systems used different methods of partitioning the disk andf the method used by DOS and early windows versions is the MBR.
MBR is old and has limited options. GTP is much more capable and is used by most modern operating systems. This includes Vista, win 7, 8, 8.1 and 10.
From your post: the ... drive reads GTP protected partition
.
This basically means that the drive uses the GPT style partition table.
Now XP is old. It does not natively understand how to read a GPT table and thus it does not recognise the disk. This leaves you with three options:
- Find or write a driver for XP.
- Use different operating system which understands GPT.
- Take a backup and convert the disk to MBR. This might not work if the disk is > 2TiB.
For option 3 first success in options 1 or 2 to make a backup. Catch 22...
Easiest solution: Download a live CD and mount both disks. Then copy the data. If you need to keep using the GPT drive on XP then you can clean it or convert it. However considering that XP is no longer supported you might also simply want to upgrade the XP system.