1)Restart computer correctly (close all programs before you Restart computer).
2)Open Disk Management in Windows 8 (right-click Computer, select Manage, click Disk Management).
Right-click your CD/DVD drive(s), select Change drive letter and paths..., and click Change.
Change the drive letter to K (get it out of the way!).
Right-click the Windows 8 Volume (probably C:), and select Properties.
In the General tab, enter wn_8 as the label for the Windows 8 volume, and click Apply.
3)In Disk Management in Windows 8
Right-click the wn_8 volume, and click Shrink Volume.
In Enter the amount of space to shrink in MB: enter enough for XP (and maybe a Data drive).
Click the Shrink button (it may take some time!).
We will leave the newly acquired free space as Unallocated (preferred) or RAW (unformatted).
If Shrink does not give you sufficient Unallocated space, read how to Shrink the Windows 8, 7 or Windows Vista Partition for instructions or use the free GParted Live CD. Then return here.
Do this next part ONLY if you want to create a size-specific unformatted (RAW) partition for XP.
Right-click the Unallocated space and select New Simple Volume.... Click Next.
In Specify volume size:, enter the size you want in MB and click Next.
In Assign Drive letter or Path, just click Next.
In Format Partition, do not Format - select Do not format this volume in the drop-down.
Click Finish button.
If you have a very large hard disk, you can create an extra partition for data - now or later.
(Disk Management will automatically create Logical partitions when those become necessary).
4)Restart to Windows 8.
Open Disk Management and check that the change made is correct.
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