Microsoft defender security locked my computer can't do anything

Slowride Pellechio 0 Reputation points
2026-08-28T21:09:17.49+00:00

I received error message saying Microsoft defender security center found infected files. It locked my computer can't do anything. the pointer is gone I can't do anything. Q&A says to download a fix it but I can't click anything. I shut down my computer and restarted. I went to settings and was looking for update & security then the error message popped up again. Help tech support

Microsoft Security | Microsoft Defender | Other
0 comments

1 answer

Sort by: Most helpful
Most helpful Newest Oldest

  1. AI answer

    2026-08-28T21:09:33.6266667+00:00

    This is most likely a browser-based scam page, not a real Microsoft Defender lock. Do not call any phone number shown in the message, do not enter any information, and do not allow remote access.

    Try these steps in order:

    1. Press Ctrl+Alt+Del.
      • If the screen appears, open Task Manager and end browser processes, or close all browser items.
    2. If that does not work, press Alt+F4 to try to close the current window.
    3. If the browser is still stuck, restart the PC.
      • It is safe to restart even if the message says not to.
    4. After restart, open Windows Security and run a scan:
      • Start > Settings > Update & Security > Windows Security > Virus & threat protection
      • Under Current threats, select Scan options
      • Run a Full scan
    5. If the same threat keeps returning, run Microsoft Defender Offline.
      • Start > Settings > Update & Security > Windows Security > Virus & threat protection
      • Under Current threats, select Scan options
      • Select Windows Defender Offline scan > Scan now
      • Save work first, because the PC will restart before the scan starts.
    6. If Defender keeps encountering scan or removal errors:
      • Run Windows Update to make sure the latest components are installed.
      • If update errors continue, install the latest protection updates manually.
    7. If a threat is shown as partially removed:
      • Press Windows key + R
      • Run %windir%\system32\mrt.exe
      • Follow the prompts to scan and clean the PC
      • Restart, then install the latest updates

    If the pop-up appears again immediately when browsing, avoid the site that triggered it. Repeated reappearance can also indicate hidden malware, which is why the offline scan is the next step.

    References:

    AI-generated content may be incorrect. Read our transparency notes for more information.

    Was this answer helpful?

Your answer

Answers can be marked as 'Accepted' by the question author and 'Recommended' by moderators, which helps users know the answer solved the author's problem.