From the time you turn on the Power of your computer to when your desktop is available, there are hundreds of possible startup error messages you will meet if your computer has trouble in booting. Here we just list some messages which seem to show up commonly. Have an error other than one listed above? No problem, you just aren't experiencing one of the more common computer startup error messages.
And all the boot issues that the startup error messages are indicating can be fixed by using a useful program – That's Windows Boot Genius. It thoroughly, safely and easily solves all the possible boot issues when your Windows won't start.
Disk Boot Failure, Insert System Disk and Press Enter
Even though you have inserted the proper disks time after time, you still can't login into Windows and see this message "Disk Boot Failure".
It occurs after a new application or device drive has been installed or updated if an application was originally loaded from a disk but its information becomes outdated. Virus attack or wrong settings are also blame to a disk boot failure.
Operating System not Found
When you turn on your computer, it stops at this error and appears "Operating System not Found"before Windows has had a chance to load. Either it locks up while not responding to the further input from the keyboard or the computer restarts on its own.
It reflects that some critical system files have been corrupted or damaged. Or hardware has problems.