When you move a dynamic disk from one computer to another this dynamic disk is flagged in Disk Manager as a foreign disk. In order to access this foreign disk you must import it first.
To Import the Foreign Disk on Windows XP
1. Click Start
2. Control Panel
3. Administrative Tools
4. Computer Management
5. Disk Management
6. Right click on the Foreign Disk
7. Select "Import Foreign Disk"
What if the "Import Foreign Disk" option is not present.
If you right click on the foreign disk and the "Import Foreign Disk" is not present, this can happen because the dynamic disk was from a Windows XP Pro machine and the new machine has Windows XP Home installed. Windows XP Home cannot read dynamic disks as they do not have a normal partition table.
Convert to Basic Disk
To make the disk accessible to the new machine you will need to convert it to a basic disk. However this process will destroy the data on the disk.
What to do
If this is the case, you will need to put the disk back into the original machine and then remove all the data or the most valuable data to another location such as a writable DVD, another hard disk drive present on the old machine, USB thumb drive / memory disk, tape back or another machine on your network (if you have one) then you can convert it to a basic disk in the new machine and put the data back on it.