The solution of the boot files and the boot option Menu are lost after Windows XP dual operating systems reinstalled:
1.Install Windows XP in Windows 7 to make up of a dual system.
2.Windows XP Windows 7 dual system, reinstall Windows XP.
3.Windows 7 Windows XP dual system, reinstall Windows 7.
All of the actions will inevitably destroy the boot files and the options menu.Therefor there will be the anomaly only enter one system . Solve the problem, simply run a small tool BCDautofix the boot files and the options menu could be repaired, thus solved the anomaly successfully, there are two system boot options, enter and run all right.
You can download the BCDautofix tool here http://www.computerites.com/bcdautofix
This address is http://www.computerites.com/computer-skills/2011/12/solution-of-the-boot-files-and-the-boot-option-menu-are-lost-after-windows-xp-windows-7-dual-system-reinstalled-216.html