Is your computer stuck on a black screen with blinking underscore/cursor and unable to boot into Windows? If yes, you’ve come to the right place. Here this post on MiniTool shares several proven fixes to help you address this problem and regain access to your files.
Phenomenon: PC Is Stuck on Black Screen With Blinking Underscore/Cursor
For various reasons, you may encounter a situation where Windows fails to boot properly and gets stuck on a black screen with a blinking underscore/cursor. This terrible phenomenon will prevent you from accessing your files on the computer or performing other operations. Generally speaking, this problem may be related to unstable power supply, boot record corruption, improper configuration of CSM, damaged graphics driver, etc.
Faced with blinking underscore on boot, you don’t have to panic too much. You can take the following methods to fix it.
How to Fix Black Screen With Blinking Underscore Windows 10/11
Way 1. Unplug the Power Cord
When faced with various types of black screen problems, you can first check the connection to rule out interference from external hard drives and unstable power supply. You can unplug the power cord and reconnect it firmly to ensure a stable connection. In addition, you should remove all external hard disks or other USB devices. If you are familiar with computer hardware, you may also consider reconnecting your hard drives, graphics cards, and memory sticks.
Way 2. Update Bootcode
If the black screen with blinking cursor/underscore is not associated with the connection, you can follow the steps below to update the boot code for your disk volumes.
Step 1. On a working computer, download the Windows Installation Media Tool and use it to create an installation USB disk.
Step 2. Boot the problematic computer, and during this process, press Esc, F8, Delete, or another target key (depending on your computer manufacturer) to enter BIOS. Next, select to boot from the installation USB disk.
Step 3. When you see the Windows Setup window, click Next. Then choose Repair your computer from the lower left corner.
Step 4. When you see the Choose an option window, click Troubleshoot > Command Prompt.
Step 5. In the command line window, type diskpart and press Enter.
Step 6. Type list volume and press Enter. When all the volumes are listed, type exit and press Enter.
Step 7. Type cd /d d:/boot (d represents the drive letter of the USB drive) and press Enter. After that, type dir and press Enter.
Step 8. Type bootsect.exe /nt60 SYS /mbr and press Enter. Alternatively, you can execute bootsect.exe /nt60 C: /mbr or bootsect.exe /nt60 ALL.
Step 9. When the “Bootcode was successfully updated on all targeted volumes” message appears, type exit and press Enter.
Step 10. Click Continue and start your computer as normal.
Way 3. Disable CSM
Although CSM helps old operating systems and software run on UEFI-enabled hardware, it can sometimes cause compatibility issues, resulting in a black screen with blinking underscore. If your system and all hardware fully support UEFI, you can try disabling CSM to resolve these compatibility issues.
The steps to disable CSM vary from computer brand to brand. Typically, you should restart the computer and press the appropriate key, such as F2, F10, Del, etc. to enter BIOS. Then find the CSM setting in the BIOS menu, set CSM to disabled, and save the change.
Way 4. Uninstall and Reinstall the Graphics Card Driver
To fix the corrupted graphics card driver that causes the black screen with blinking underscore, you can uninstall the driver and reinstall it.
- Right-click the Start button and choose Device Manager.
- Expand Display adapters, right-click your device, and choose Uninstall device. Then follow the on-screen instructions to uninstall it completely.
- Go to the official website of your graphics card manufacturer to download the latest driver, and then install it on your computer.
Verdict
You should have resolved the black screen with blinking underscore/cursor after applying the methods above. If, unfortunately, the black screen persists and there are important files on the computer, you can use MiniTool Power Data Recovery Bootable Edition to rescue your files without booting Windows. You can click the button below to download the free edition and then upgrade it.
The above is the detailed content of Worked! Fix the Black Screen With Blinking Underscore/Cursor. For more information, please follow other related articles on the PHP Chinese website!

Offsite VM backups are crucial. This guide demonstrates how to easily copy ESXi virtual machines to a USB drive for secure, accessible storage. Method 1: Manual VM File Download This method copies the core VM files. Power off the target VM in the V

This non-security update, KB5055612 for Windows 10 version 22H2 and related versions, released April 22, 2025, offers several quality improvements. This guide details installation and troubleshooting steps. KB5055612: Key Improvements This update enh

Troubleshooting KB5055642 Installation Problems on Windows 11 This guide offers solutions for users encountering issues installing Windows 11 Insider Preview Build 26200.5562 (KB5055642), released April 21, 2025. This update introduces enhanced featu

Updates are vital to ensure that a Windows system runs well and is protected from potential outside threats, such as software vulnerabilities. Unfortunately, Wi

Encountering the Steam "Invalid Platform" error? This MiniTool guide offers several solutions to get you back in the game. This frustrating error typically means your game is incompatible with your operating system. Understanding the Error

The Windows Xbox app lets you manage your Game Pass library, view friends, and launch PC games from one place. Its a hub of Microsofts gaming experience, especi

VMware Workstation on Windows 11: Troubleshooting Slow Performance Experiencing sluggish system performance after installing VMware Workstation on your Windows 11 desktop? This guide offers practical solutions to resolve this common issue. Quick Nav

Many players have encountered frustrating low FPS, stuttering, and lagging issues in Oblivion Remastered. This MiniTool guide offers several effective solutions to boost your gameplay performance. Quick Navigation: Oblivion Remastered Performance Pr


Hot AI Tools

Undresser.AI Undress
AI-powered app for creating realistic nude photos

AI Clothes Remover
Online AI tool for removing clothes from photos.

Undress AI Tool
Undress images for free

Clothoff.io
AI clothes remover

Video Face Swap
Swap faces in any video effortlessly with our completely free AI face swap tool!

Hot Article

Hot Tools

SublimeText3 Linux new version
SublimeText3 Linux latest version

SAP NetWeaver Server Adapter for Eclipse
Integrate Eclipse with SAP NetWeaver application server.

SublimeText3 English version
Recommended: Win version, supports code prompts!

PhpStorm Mac version
The latest (2018.2.1) professional PHP integrated development tool

VSCode Windows 64-bit Download
A free and powerful IDE editor launched by Microsoft
