Problems in the Windows Boot Manager will prevent the computer system from starting after a fresh installation of the Windows 7 operating system. The Windows 7 operating system will fail to start the session manager before rebooting and throw an error message during the boot procedure. The issue can be solved by deleting the 100mb partition which is reserved for the system. If Windows refuses start and the error persists, all partitions may have to be deleted and the installation process repeated to fix the Windows Boot Manager error.
During the final phase of the installation of Windows 7, Windows tells you it failed to start the session manager before restarting and you see the following message at boot.
If after reinstalling Windows, it refuses to boot a prompt you with the following error message
Run the installation CD, proceed with the installation until it asks you on which partition to install Windows and from there delete the partition "Reserved for System" which is 100mb. If your problem is not resolved, delete or format any partition and retry the installation.