Troubleshooting Boot Issues

When troubleshooting boot issues, you should determine the failure point.

Failure to Boot/Invalid Boot Disk

if firmware returns error message like “No boot device found” or “invalid boot disk”, then the system has failed to boot
most common cause is USB is set as boot device
change boot device priority/boot order to the hard disk
- if message still occurs, check connections to the drive
- if error is transitory, then disk could be failing
if older system, firmware could have trouble detecting the drive

message can appear when a disk drive is identified as the boot device but does not report the location of the OS loader
could indicate a faulty disk
- run disk diagnostics
- use recovery option to run chkdsk
if disk cannot be detected
- enter system setup and modify settings/resetting to default
if disk is detected, but Windows wont boot
- use startup repair tool to open recovery mode command prompt
- use bootrec tool to repair drive boot information
  - bootrec /fixmbr to attempt repair of the MBR
  - bootrec /fixboot to attempt repair of the boot sector
  - bootrec /rebuildbcd to add missing Windows installations to the boot configuration database (BCD)
use diskpart to ensure system partition is marked as active and no others are

likely causes are corruption of drivers or other system files
if system can boot to GUI in Safe Mode
- replace graphics adapter driver
if system will not boot to a GUI in Safe Mode
- Windows installation will have to be repaired or recovered from backup
- possible that boot config has been changed in msconfig and needs to be set back
Windows is prone to black screen issues, often during updates
- just wait for the update to complete
- look for signs of disk activity and spinning dots
WINDOWS+CTRL+SHIFT+B to test if system is responsive
- beep and display may reinitialize
if problem occurs frequently
- use chkdsk and sfc to verify system file integrity
- update or rollback graphics adapter driver