Microsoft’s latest Windows 11 update—KB5063878, released on August 12, 2025—is under scrutiny for causing SSD failures and data corruption. If you’ve recently updated to version 24H2 (Build 26100.4946), here’s what you need to know to protect your data and your sanity.
🧨 What’s Going Wrong?
After installing KB5063878, some users—especially in Japan—reported that their SSDs suddenly vanished from Windows. In many cases, the drives showed up as “RAW” partitions, meaning they were unreadable by both Windows and BIOS.
This issue typically occurs when:
- The SSD is more than 60% full
- A large file (50GB+) is written continuously (e.g., during game updates like Cyberpunk 2077 or Honkai: Star Rail)
- The drive uses certain NAND controllers (Phison, InnoGrit, Maxio), though it’s not brand-specific
🔍 Why It’s Happening
The bug appears to stem from how Windows 11 handles write caching and buffering. Under heavy write loads, the SSD controller may become overwhelmed, triggering a reset or complete failure. In severe cases, the drive becomes unresponsive and data recovery may require advanced tools or full erasure.
🧪 Who’s Affected?
While the issue is real, it’s rare. Microsoft estimates only a few thousand users may be affected, and only a few hundred have likely noticed it. Still, if your workflow involves large file transfers or game updates, you could be at risk.
🛡️ What You Can Do
Here’s how to stay safe:
- Check your OS version: Go to Settings > System > About and confirm if you’re on Build 26100.4946.
- Pause updates: If you haven’t installed KB5063878, consider pausing updates for 7 days.
- Avoid heavy writes: Don’t install large games or transfer massive files until Microsoft releases a fix.
- Backup your data: Always keep backups—especially before installing updates.
- Report issues: If you’re affected, use the Feedback Hub to help Microsoft investigate.
🧠 Final Thoughts
This bug isn’t tied to any specific SSD brand—it’s a Windows-level issue. Microsoft is actively investigating with hardware partners like Phison, but no official fix has been released yet. Until then, caution is your best defense.
Image credit: Microsoft Malaysia News Center