Windows 7 boot process wiki

During this subphase, the kernel initializes data structures and components. During WinLogonInit, the user logon screen appears, the service control manager starts services, and Group Policy scripts run. WinLogonInit ends when the Explorer process starts. The ExplorerInit subphase begins when Explorer.

During ExplorerInit, the system creates the desktop window manager DWM process, which initializes the desktop and displays it for the first time. A detailed analysis of each phase would go far beyond the scope of this article.

Common performance vulnerabilities are described in the whitepaper as well. Still, it might require more tools like parallel network traces and additional debug logs such as Gpsvc logging to fully analyze a problem.

If the WinLogonInit phase takes a long time, you can use the Winlogon graph for further analysis. In this example the Group Policy processing took around seconds to complete, before the Windows desktop could be loaded. While the Winlogon graph does not explain why it took seconds to complete GPO processing which could be related to network issues, policy settings, GPO preferences, scripts, and so on , your can see where to investigate further.

The PostBoot phase includes all background activity that occurs after the desktop is ready. The user can interact with the desktop, but the system might still be starting services, tray icons, and application code in the background, potentially having an impact on how the user perceives system responsiveness.

One way to analyze the prefetcher activities is to run xperf. The above should give you some insight into where to start looking for issues during the Windows boot phase, as it will help you identify the correction section to start troubleshooting.

Method 1. Backup your files. The installation process will delete all data on your hard drive. It is recommended that you back up all files you want to keep before installing a new operating system.

You can backup your files to another hard drive, an external hard drive, a flash drive, or a cloud-based service like Google Drive, or Dropbox.

Restart your computer. Press the power button on your computer and then click Restart in the power options menu. Depending on the make and model of your computer, pressing one of these buttons immediately after you power on your computer will enter the system BIOS.

Some computers tell you which button to press to enter the BIOS as the computer starts up. Find your BIOS's boot options menu. The boot options menu of your BIOS may vary in location or name from the illustration, but you may eventually find it if you search around.

Select the optical disk drive as the first boot device of your computer. Although this method may vary among computers, the boot options menu is typically a menu of movable device names where you should set your CD, DVD or Blu-ray drive as the first boot device.

It can also be a list of devices that you can set the order of their boot on. Consult a manual or the internet for help if you're stuck. Place the Windows 7 Installation disc in the disc drive. Then place the Windows 7 installation disc in the disk tray and push it back in the drive. Save the changes in the settings. Press the button indicated on the screen or select the save option from the BIOS menu to save your configuration.

Shut off your computer. Either turn off the computer by choosing the shut-down option in your current operating system, or hold the power button until the computer powers off. Start your computer from the disc. After you have placed the disc into the disc drive, start your computer. When the computer starts, press a key if you are asked if you would like to boot from the disc by pressing any key. After you choose to start from the disc. Windows Setup will begin loading. If you are not asked to boot from the disc, you may have done something wrong.

Retry the previous steps and make sure you have selected the correct drive in the BIOS boot menu. Choose your Windows Setup options. Once Windows Setup loads, you'll be presented with a window.

Click the Install Now button. It's the blue button in the center of the screen. Accept the License Terms. Read over the Microsoft Software License Terms. Then click the checkbox next to I accept the license terms , and click Next in the lower-right corner. Select the Custom installation. This option allows you to do a clean install of Windows 7.

This will erase all your files on the installation drive. If you do not want to erase all your files, select Upgrade instead. This option requires an existing Windows installation. You can only upgrade from one Windows edition to another. You would not be able to upgrade to Windows 7 Home Premium. Select a hard drive and partition you want to install Windows on. A hard drive is a physical part of your computer that stores data, and partitions "divide" hard drives into separate sections.

Click the hard drive or partition you want to install Windows 7 on. If the hard drive has data on it, You'll need to use the following steps to Delete or Format the drive.

Be aware that this will permanently erase all data from the disk. Select the hard drive from the list of hard drives. Click Drive options advanced. Click Delete or Format from Drive options. If your computer doesn't have any partitions yet, create one to install Windows on it.

Select New from Drive options. Select the size, and click OK. Install Windows on your preferred hard drive and partition. Once you've decided on where to install Windows, select it and click Next. Windows will begin installing. Your computer may start and restart several times during the installation process.

Method 2. Start your computer. Boot up your computer as normally into your current operating system. Check to see if your computer is compatible with Windows 7. The Windows 7 Upgrade Advisor scans your computer to see if you can upgrade it to Windows 7. In order to upgrade to Windows 7, you must upgrade to the same version of Windows you already have.

Prepare your computer to install Windows. Use the following steps to prepare your computer for a Windows installation: Back up your files. It's a good idea to back up any files you want to keep in case there is a problem during the upgrade. You can back up for your files using another hard drive, an external hard drive, a flash drive, or a cloud service such as Google Drive or Dropbox.

Scan your computer for malware. Malware can prevent Windows from installing correctly. Disable or uninstall any antivirus software because they may interfere with the Windows installation.

Uninstall some unnecessary programs to speed up the upgrade. You can install them after Windows 7 has finished. Update Windows with Windows Update. Delete some unnecessary files to speed up the upgrade. Back up your hard drive in case the installation fails and you lose your files.

Insert your Windows 7 installation disc. Click the Windows Start menu. By default, it's the icon with the Windows logo in the lower-left corner. Alternatively, you can boot your computer from the disc as outlined in Method 1 and select Update from the installation screen. Click My Computer. This is displays all drives on your computer. If you are using a newer version of Windows, click Windows Explorer. The goal of this article is to give readers an overview of the Windows boot process so that you can better troubleshoot a slow OS start or slow user logon that is caused by delays in the OS boot process.

R elated problems about resuming from sleep, wake from hibernate, or OS shutdown processes are not covered in this article. During the OS Initialization phase, most of the operating system work occurs. This phase involves kernel initialization, Plug and Play activity, service start, logon, and Explorer desktop initialization.

The OS Initialization can be divided into four subphases. Each subphase has unique characteristics and performance vulnerabilities. During this subphase, the kernel initializes data structures and components.

During WinLogonInit, the user logon screen appears, the service control manager starts services, and Group Policy scripts run. WinLogonInit ends when the Explorer process starts. Sub phase 4 — ExplorerInit: Explorer Initialization.

The ExplorerInit subphase begins when Explorer. During ExplorerInit, the system creates the desktop window manager DWM process, which initializes the desktop and displays it for the first time. A detailed analysis of each phase would go far beyond the scope of this article. Common performance vulnerabilities are described in the whitepaper as well.