Performing an in-place upgrade of your operating system or Reinstalling the Windows OS is an extreme troubleshooting way that you must only take if you entirely understand the implications and risks concerned.
If you are not comfortable trying to reinstall or restore the Windows OS, you might want to bring your computer to a professional repair shop or contact your computer producer for help. If you choose to receive this step, make sure that you have the original Windows XP installation media and their product key that was contained with operating system.

This news explains two types to execute an in-place improvement (reinstallation) of Windows XP. An in-place upgrade is also known as a repair installation. This operation reinstalls Windows XP to the same folder on your computer where it was originally installed. You might feel to execute an in-place upgrade if your installation of Windows XP must be renovated and if one of the following circumstances is exact:
1. You cannot start Windows XP in safe mode.

2. You cannot start Windows XP after you install a Microsoft software update.


3. There is a registry problem that cannot be solved by using other tools such as System Restore.

4. You must apply default (file and registry) permissions to your Windows XP installation. This condition can occur if program files are missing or damaged after you make changes or updates to your computer or programs.


5. You must register COM components and Windows File Protection (WFP) files. This condition occurs because of missing or damaged system files.

6. You must use the Windows Setup program to enumerate Plug and Play devices again. This includes the hardware abstraction layer (HAL).