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You sit down at your computer, push the power button just like you do every day, and...nothing happens. Maybe the computer doesn't turn on at all, or it could power up but shut right back down. As far as you're concerned, there's nothing obviously wrong here, so why won't the computer just start? Before you panic, or begin looking for a new laptop to buy , let's first make sure this isn't something you can fix yourself. Here are some troubleshooting steps that can help narrow down the issue.
1. Give It More Power
Are you sure the computer is charging ? If the machine isn't turning on at all—no fans are running, no lights are blinking, and nothing appears on screen—you probably have a power issue. Plug your computer directly into a wall outlet you know is working, rather than a power strip or battery backup that may be failing. Make sure the power switch on the back of your power supply is flipped on, and if the outlet is connected to a light switch, make sure that switch is turned on too.
If you're using a laptop, make sure the charger is plugged in properly and to the correct port—if it charges via USB-C , only some of the USB ports may actually provide power. A failing power supply can often cause boot problems, even if the fans and lights do turn on. So if the troubleshooting steps in this guide fail you, it might be time to replace your power supply.
2. Check Your Monitor
If the computer sounds like it's turning on but you don't see anything on the screen, the computer may be booting and the monitor just isn't showing an image . Check to make sure your monitor is plugged in (again, try a wall outlet instead of a power strip), turned on, and set to the right input using the buttons on the side or bottom. Make sure the cable connecting the monitor to your computer hasn't come loose, become damaged, or is in any way at fault.
To completely rule out a problem with the monitor, plug your PC into another display— or even a TV —and see if you can get a picture that way. If you can, it's possible you need a new monitor . And this may sound silly, but make sure the brightness is turned up on your laptop. I've had multiple people ask me for help with a computer that won't start, only to find the brightness was turned all the way down, creating a black screen.
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3. Listen for the Beep
When your computer boots, it may make a beeping sound—usually a single beep means everything is A-Okay. But if the computer is having trouble starting up, it may make a series of beeps (kind of like Morse code) that tell you what's wrong. Check the manual for your computer (or the PC's motherboard , if you built it yourself ) and figure out what the beeps mean. If you don't have your manual, you can probably find it on the manufacturer's website.
If your computer doesn't beep at all, you might be out of luck, though some desktop PCs may have a header on the motherboard where you can install a cheap speaker , or even a digital display with a numerical code that corresponds to an error message.
4. Unplug Unnecessary USB Devices
Before continuing, unplug anything superfluous from your computer— webcams , USB headsets, external hard drives , etc. Try booting with just a keyboard and mouse (or even without them, if in dire straits) to see if one of your USB devices is causing a conflict.
In some circumstances, it may not even be the device itself, but the port on your computer . I've owned a PC that couldn't get into Windows if something was plugged into the front USB port—once booted, the ports would work fine, but it needed to be empty during the boot process. The more variables you can eliminate, the better.
5. Reseat the Hardware Inside
There's a chance a component of your computer has come loose inside the case, especially if it was recently transported somewhere or if you were working inside it. If you're comfortable opening the computer up, remove the side panel and make sure the components are properly seated in their respective sockets.
Pay special attention to components like your RAM , graphics card , motherboard cables, and heatsink. Remove these items completely, then plug them back in, ensuring they click in all the way. You might also try booting without certain hardware, like the graphics card or one of the RAM sticks, in case they're faulty. (And if it doesn't work with one RAM stick, try the other.)
6. Explore the BIOS
Does your computer only show the POST screen but can't boot into Windows? Certain settings may be causing the problem. For example, an error stating that your computer can't find a bootable operating system may mean your BIOS is set to boot from the wrong drive or your overclock settings are causing the computer to blue screen immediately. Enter your BIOS when the POST screen appears, usually by pressing Delete, F2, or some other key to enter setup.
If you've tweaked any of these settings recently, try changing them back. Make sure your Boot Order is set to the correct hard drive, your RAM is recognized, and that your CPU isn't overheating (if it's above 90 degrees Celsius in the BIOS, something is definitely wrong). You might also turn off the Fast Boot feature, in case a recent Windows Update is conflicting with it.
If all else fails, try resetting your BIOS settings across the board using the Load Optimized Defaults option. Just be sure to snap a few photos of your BIOS settings so you can set them back if that doesn't work.
7. Scan For Viruses Using a Live CD
It's possible you have some nasty malware that's preventing your computer from booting. But with a live environment like Hiren's Boot CD , you can boot your computer from a CD or USB drive and scan the drive for malware without booting into Windows. Download the ISO image from this page , and follow the instructions to "burn" it to a USB flash drive.
Reboot your computer and access the Boot menu—usually by pressing F11, F12, or some other key defined at startup. Choose your USB drive from the boot menu, and it should boot into Hiren's live environment. From there, head into Utilities > Security and run a virus scan with ESET and a malware scan with Malwarebytes . If either program finds anything, it'll let you know and attempt to fix it, which will hopefully allow you to boot into Windows once again.
8. Boot Into Safe Mode
If you're getting the Blue Screen of Death at startup, it could be a bad application, driver issue, or hardware quirk causing the problem. Do a web search for the stop code that appears and see if it gives you any insight into what's wrong. Chances are, though, you'll have to boot into Safe Mode to fix the problem. This is harder than it used to be, but if you interrupt the boot process three times—say, by pressing the reset button as Windows tries to boot—it will take you to the Automatic Repair screen, where you can click Advanced Options.
Alternatively, you can create a Windows installation drive using another PC and boot from that directly, choosing your language and selecting Repair Your Computerwhen given the option. Either of these methods should eventually get you to the Choose an Optionscreen, where you can click Troubleshoot > Advanced Options > Startup Settings and reboot the computer. (If you don't see the Startup Settings option, you may need to click See More Recovery Optionsalong the bottom.)
Your computer should then give you the option to boot into Safe Mode, Safe Mode with Networking, or Safe Mode with Command Prompt. You can try any of these, though Safe Modeis probably your best bet, or Safe Mode with Networkingif you need to access the internet. This will load Windows with only the most crucial drivers and services running.
If you installed any new hardware recently, try uninstalling its drivers from Safe Mode. If you think a new application might be to blame, get rid of that too. BlueScreenView can help you look back through your most recent Blue Screens of Death to see the file that caused the problem, or any bug check strings and codes to look up.
9. Roll Back a Problematic Windows Update
If you recently installed a Windows Update—or the OS updated in the background on its own—it may have caused a conflict that rendered your computer inoperable. It's annoying, but Windows does offer the option to roll back to the previous version , even if you can't get into Windows itself.
Head back to the Troubleshoot > Advanced Options menu using the instructions above, then choose Uninstall Updates. Try uninstalling the latest Quality Update or Feature Update. If you're lucky, this may get you back into Windows, at which point you can delay Windows updates until the kinks are worked out.
10. Check Your Hard Drive for Corruption
It's possible some data on your drive is corrupt, preventing Windows from booting properly. Thankfully, Microsoft has a few tools that can attempt to fix the problem. Head to the Troubleshoot > Advanced Options menu as described above and choose Command Prompt. Type the following command and press Enter:
This will tell Windows to check your drive for corruption and attempt to repair any problems. You can do a broader search for file corruption and bad sectors by entering the following:
If you have multiple drives, there's another command you can run (just replace the drive letter with the correct one from the resulting list):
11. Repair a Busted Boot Loader
Sometimes your Windows installation is fine, but the boot loader—the data that governs Windows' boot process—is corrupted. This often happens if you clone your hard drive , create a new drive partition , or dual-boot Linux and mess something up along the way. You'll often get a message saying "Error loading operating system," "Invalid partition table," or "FATA: No bootable medium found! System halted."
If you have a good backup , you can try to repair the boot loader using Windows' built-in tools by going to Troubleshoot > Advanced Options as described above, then choosing Startup Repair. I wouldn't attempt these steps unless your files are backed up , as messing with partitions can always risk the loss of data. You can also run the Command Prompt from this menu and try running one of the following commands:
If that doesn't work, repairing the boot loader may be more complicated due to newer EFI boot loaders— you can see instructions on doing so here —but it may be easier and faster to reinstall Windows from scratch and restore from a backup.
12. Test the Drive in Another PC and Pray
If all else fails, and you don't have a backup, take your storage drive out of the computer, connect it to a USB adapter , dock , or enclosure , and plug it into another known working PC. If you don't have another PC, try booting from a Linux Live CD on your current machine. As long as the drive is still working—a big "if"—you can at least copy your files onto an external drive for safekeeping before reinstalling Windows or sending the PC in for repairs.
