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Restart your PC, then try repairing Windows Security from Settings. If Repair is unavailable or does not help, use Reset if Windows offers it. Back up important files before attempting recovery or removing an update. A Windows Security window that will not open does not, by itself, establish whether antivirus protection is active.
Start with a restart and try Windows Security again
Save your work and restart Windows. Then open Start, type Windows Security, and select the app. Microsoft describes Start as the normal way to open Windows Security: Stay protected with Windows Security.
If the app still fails to open, continue with the app-level options below. The timing may suggest a connection to an update, but the available Microsoft guidance does not identify a specific update or confirm that an update caused this symptom.
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Try Repair, then Reset if Windows offers it
Repair is the less disruptive app-level option. The Settings path differs by Windows version, and these controls are not available for every app. Follow the path for your version, and proceed only if Windows displays the options.
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- Windows 11: Open Settings > Apps > Installed apps. Find Windows Security, select its menu, and open Advanced options if shown.
- Windows 10: Open Settings > Apps > Apps & features. Select Windows Security and choose Advanced options if shown.
- Select Repair, if available, and try opening Windows Security again.
- If Repair is missing or does not fix the problem, select Reset if available, then try opening the app again. Microsoft’s guidance is: “If it isn’t available or doesn’t fix the problem, select Reset.” See Repair apps and programs in Windows.
Reset may change the app’s data or settings, so try Repair first. If neither option appears, skip this step rather than searching for unrelated settings or tools.
Check protection without assuming the app failure means antivirus is off
Windows Security is an interface for security providers. Its failure to launch does not prove that antivirus protection is disabled, and the cited Microsoft documentation does not establish protection status from this symptom alone. If another security-provider interface on the PC opens, use it to check protection status. If you cannot verify that the PC is protected, contact qualified support or your organization’s IT team rather than assuming either that protection is on or that it is off.
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Back up important files before recovery
Before using Windows Recovery Environment or other system recovery options, copy important files to a safe destination. Microsoft recommends backing up personal files before troubleshooting or recovery; a USB drive is one option. You can use an existing safe backup destination rather than buying new storage. A backup protects your files; it does not repair Windows Security.
Do these 3 things before closing this tab:
1Repair Windows errors before they cause bigger problems2Fix the driver behind crashes, sound loss and screen glitches3Clear out junk files and repair common Windows errorsConsider uninstalling the latest quality update only if the timing fits
If Windows Security stopped opening soon after a recent Windows update and the app-level steps did not help, uninstalling the latest quality update may be an option. Microsoft Support says, “If the problem started after a recent Windows update, uninstalling it might fix the issue.” That is a possibility, not a confirmed diagnosis for this particular symptom. Microsoft also cautions readers to understand the risks before uninstalling a security update.
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- Back up important files first.
- Enter Windows Recovery Environment (Windows RE). If Windows still opens, go to Settings > System > Recovery and use Advanced startup to restart into the recovery options.
- In Windows RE, select Troubleshoot > Advanced options > Uninstall Updates.
- Choose Uninstall latest quality update and follow the on-screen instructions. The available recovery choices and screens can vary by device.
Review Microsoft’s Recovery options in Windows and Uninstall Windows updates guidance before proceeding. Removing a security update can reduce protection while it is absent; do not use this as a routine first step or leave the system without a plan to restore current updates.
Use DISM and SFC only as general system-file troubleshooting
Microsoft’s general Windows update troubleshooting guidance documents DISM and System File Checker (SFC) for repairing possible system-file problems. It does not identify these commands as a specific fix for Windows Security failing to open. These advanced steps are intended for people comfortable using the command line.
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- RESPONSIVE MULTITASKING & STORAGE: Built with 4GB LPDDR4 RAM and 128GB eMMC storage for smooth daily essential use. Expand your storage by up to 1TB via the integrated TF card slot to easily store movies, photos, and working files
- ADVANCED CONNECTIVITY: Outfitted with 2x Full-Featured Type-C ports for data transfer, fast charging, and dual-monitor output, alongside 2x USB 3.2 Gen1 ports and a 3.5mm audio jack for complete peripheral compatibility
- LIGHTWEIGHT & SILENT OPERATION: Slim and portable for effortless travel or commuting. Features a 1MP HD webcam for remote meetings, 38Wh battery with 45W Type-C fast charging, and a fanless silent design for peaceful work environments.
- Open Start, type Command Prompt, right-click it, and choose Run as administrator.
- Run
DISM.exe /Online /Cleanup-image /Restorehealthand wait for it to finish. - Then run
sfc /scannowand let the scan complete. - Restart Windows and try opening Windows Security again.
Follow Microsoft’s Troubleshoot problems updating Windows instructions. If you are uncomfortable running elevated commands, ask a qualified technician or your organization’s IT team for help.
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Standard Windows 10 support ended on October 14, 2025. Microsoft says free Windows Update software updates, technical assistance, and security fixes ended with standard support. If this PC still runs Windows 10, consult Microsoft’s Windows 10 support ends on October 14, 2025 page for the current options relevant to your device.
Quick Recap
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- 【Vibrant Display】 15.6-inch Full HD (1920x1080) anti-glare screen with 16:9 aspect ratio delivers crisp images and vivid colors – perfect for studying, watching lectures, or entertainment. Thin-bezel design maximizes viewing area
- 【Fast Connectivity & Expansion】 Equipped with WiFi 6 (802.11ax) and Bluetooth 5.2 for stable, high-speed wireless. Features 3 x USB 3.0, HDMI 2.1, Type-C (supports PD3.0 fast charging), and a TF card slot expandable up to 2TB – easily connect external monitors, mice, drives, or expand storage for all your files
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When to get help
- Contact your work or school IT team for a managed PC, especially if Windows RE is restricted or the device uses organization-managed security.
- Get qualified assistance if you cannot verify protection status, cannot access recovery options, or are unsure whether removing an update is appropriate.
- If Windows Security remains unavailable after the steps you are comfortable trying, avoid making repeated system changes without a backup and a clear recovery plan.
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