How to Add Windows XP to Windows 7 Boot Manager
1. Open an elevated command prompt.
2. Type the following to create a boot loader for Windows XP.
bcdedit /create {ntldr} /d “Windows XP”
3. Type the following to set the device to where Windows XP is installed. I used D: in this example. Replace it with the drive letter of your XP installation.
bcdedit /set {ntldr} device partition=D:
4. Type the following to set the path.
bcdedit /set {ntldr} path \ntldr
5. Type the following to add this boot loader to the boot up screen.
bcdedit /displayorder {ntldr} /addlast
6. Reboot the computer
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