Software & Apps Windows Windows Error Recovery: How to Fix It When Windows Failed to Start How to restart, troubleshoot, repair, refresh, and reinstall Windows by Andy Wolber Freelance Contributor Andy Wolber is a former Lifewire writer who has been writing about technology for 15+ years. His focus is G Suite, iOS, and nonprofit sector apps. our editorial process Twitter LinkedIn Andy Wolber Updated on June 24, 2019 Windows The Ultimate Laptop Buying Guide Tweet Share Email When a Windows laptop or desktop system fails to start, the cause may be a disconnected device, a missing file, an unsuccessful update, or failing hardware. Follow the steps below in sequence to identify and fix the problem. In most cases, a bit of troubleshooting can get your system working again, but some problems may require you to replace failed hardware. Note: All of the following troubleshooting steps apply to Windows 10 systems. The first five apply to any Windows system, including Windows 10, Windows 8, Windows 7, Windows Vista, or Windows XP. Boot sequence troubleshooting options in step 6 and above will be slightly different in older versions of Windows. Turn off your computer, wait one minute, then turn it on again. This restores access in the event that the problem was simply an unusual glitch during the startup process. See Are You Restarting Your Computer the Right Way? for step-by-step instructions, along with Why Does Restarting Seem to Fix Most Computer Problems? to learn why this often works. On a desktop system, check your connections. If you use a keyboard or mouse with a cable, unplug and then re-plug each to confirm that the devices are connected. A disconnected keyboard, for example, can cause your system to halt during the startup process. Similarly, make sure the cable from the system to the display is connected. On a desktop system, look to make sure the power indicator light is on. If you can’t see the light, it is possible that the power supply has failed. If absolutely nothing happens when you press the power button, you may need to replace the power supply. Most people will prefer to have a professional test and replace a power supply, but if you want to test it yourself, see How Do I Test the Power Supply in My Computer?. On a laptop system with an easy-to-remove battery, unplug all power cables, then remove the battery. Then, with the battery out of the system, plug in the AC power cable and connect it to your laptop. Try to start up your system. If it starts successfully, then the problem was your laptop battery. If you see any sort of display on your screen, wait a bit longer. Windows often attempts to install system, application, and driver updates during the startup process. Especially if you have an older or slower system, these updates may take a significant amount of time to install. In some particularly problematic cases, you might leave your system on overnight, then check it the next morning. Try to Start Windows with the Last Known Good Configuration. This option attempts to start the system with recent device, registry, and operating system changes reverted to settings that worked. This can allow your system to recover from a failed system or device driver update, or a misconfigured registry entry. (When Windows fails to start twice in a row, the system should give you access to the Advanced Boot Options Menu.) Update Issues If your system successfully boots with this method, you may want to hold off immediately attempting to re-apply system or device driver updates, since these updates may be the source of the problem. Check with Microsoft Support (online or on Twitter, @MicrosoftHelps) or the device manufacturer’s site for recent news or information. Run Startup Repair (also known as Automatic Repair in older versions of Windows). Startup Repair scans your system and attempts to fix missing or damaged system files. This can take more than a few minutes to complete and also may require your system to restart. In some cases, you may need to run Startup Repair up to three times to resolve startup issues. See How Do I Automatically Repair Windows Problems? for details about this process on Windows 10, 8, 7, Vista, or XP. Try a System Restore to use a recent restore point to recover your system. A System Restore will revert your system, drivers, and registry to an earlier point in time. Boot into Safe Mode with Networking, then scan your system for malware. See How to Properly Scan Your Computer for Malware for several ways to remove malware. Some signs that your system may have malware include virus warnings, notices, or other unusual messages displayed as your system starts. Refresh your PC without affecting your files. This process reinstalls Windows, but keeps apps originally installed along with apps installed from the Microsoft Store. Since it removes applications and refreshes operating system files and folders, it also can resolve problems that result from issues in either place. Refresh Removes Applications While a Refresh won’t delete your personal files, this process will remove applications you have installed. You will need to either re-download or otherwise re-install any apps you’d added from sources other than the Microsoft Store. Try a Windows Reset, which is similar to a Windows Refresh, but also deletes your files. A reset will leave you with Windows and the apps originally installed on your system. Most often, people initiate a Windows Reset when they’re ready to get rid of a system, but want to give the system to someone else. A reset wipes out system customizations and changes, removes installed applications, and deletes data. However, it can be an effective way to return a problematic system into a once-again usable computer. Reset Deletes Data Make sure you have your personal files backed up elsewhere before you do a Reset. A Reset will erase your files. See How to Fix Problems Caused by Windows Updates for detailed information on how to reset, refresh, or reinstall Windows 10, Windows 8, Windows 7, Windows Vista, and Windows XP. Check for a failed or failing drive, following the instructions in What to Do When Your Hard Drive Is Making Noise. A failed or failing drive may prevent Windows from booting properly. Hard drives with spinning parts often emit grinding or clanking sounds when they fail, while solid state drives (SSDs) typically stop working with no audible indicators. If a drive fails, you may install Windows on a new drive. If you don’t have your data backed up elsewhere, you might use data recovery software to attempt to retrieve your files from the failed drive. If none of the above steps has worked, you can try a clean install of Windows. This will erase everything on your drive and replace it with a new installation of Windows. Follow the steps at How to Clean Install Windows (Delete & Reinstall) to reinstall Windows 10, 8, 7, Vista, or XP.