This applies to Windows Vista, Windows Server 2008, Windows 7, Windows Server 2008 R2, and Windows 8. This is a common issue that occurs when the system partition (the one that Windows boots from, not where the kernel is located) of a Windows installation gets corrupted or files on the system partition are deleted (specifically bootmgr). Resolution is fairly straightforward after booting from the Windows DVD and entering recovery mode.
Open a command prompt and use diskpart to find the system volume (usually labeled "System Reserved") and identify the installation DVD for windows (Identified for most users as the one with UDF in the Fs column and DVD-ROM in the Type column). From there, the bootmgr file can be copied back into the system partition using the copy command. The bootmgr file is located in the root of the DVD drive.Rebooting the system should allow the system to boot.
Windows Crash Dump Analysis