There can be a number of reasons why you may not be able to boot your Windows system. The following are some of the most common causes that lead to this issue, and ways to troubleshoot them:
1. Incorrect BIOS Settings:
The BIOS (Basic Input/Output System) handles the basic instructions for the computer to start. It controls critical hardware components such as CPU speeds, memory, hard drives, etc. If the BIOS settings are incorrect, the system cannot boot. To fix this, restart the computer and enter the BIOS setup by pressing the appropriate key (usually F1, F2, DEL or ESC) at the start of the boot process. Look for any settings that could be causing the boot issue, such as incorrect boot order, disabled hard drive, etc. and change the settings accordingly.
2. Corrupt or Missing Operating System Files:
If the Operating System files become corrupted or deleted, Windows will not be able to start correctly. To check if this is the cause of your boot issue, try booting from a recovery disk or installation media and running a startup repair. This will scan the system to look for any corrupt or missing files and attempt to replace them with healthy versions.
3. Hard Drive Failure:
Another cause for a boot failure may be due to problems with the Hard Drive itself. If the hard drive becomes damaged or corrupted, it can cause the computer to not boot. You can diagnose the hard drive by running a diagnostic utility or connecting the drive to another computer and running a diagnostic tool from there. If the hard drive is damaged, you may need to replace it.
4. Bad Memory:
Bad memory can also cause a boot failure. If the memory is bad, the computer may not be able to access the necessary data to boot up properly. To diagnose bad memory, you can test the RAM using a diagnostic utility such as memtest86+. If the RAM is found to be bad, you will need to replace it.
5. Overheating:
Overheating can also cause boot issues as the computer will shut down in an attempt to protect itself from damage. To diagnose this issue, you should check the temperature of the components inside the system such as the CPU and GPU. If they are higher than normal, the system may be overheating and the fan or air intake may need to be cleaned or replaced.
6. Boot Sector Virus:
A Boot Sector virus can also cause the system to not boot up correctly. To check for this, you can use an antivirus to scan the system for any malicious software. It may also be possible to boot into Safe Mode, which can help avoid any malicious software running before it can cause any issues.
7. Bad Power Supply:
Finally, a bad power supply can also cause a boot failure as it does not provide the correct power to the components inside the computer. To diagnose this, you should check the voltage using a multimeter and make sure it is within the recommended range. If the voltage is too low, you may need to replace the power supply.
In conclusion, there are many potential causes of a boot failure on a Windows system. To troubleshoot the issue, it is important to check the BIOS settings, operating system files, hard drive, memory, temperatures and power supply to ensure they are all functioning correctly and that there are no malicious programs present. After making any necessary changes, restart the computer and it should boot up correctly.