Concerns that Windows 11’s August security update, KB5063878, could be damaging SSDs have prompted an official response from Microsoft. Some users alleged that after installing the patch, their drives disappeared entirely from File Explorer and BIOS or reappeared as “RAW” partitions, effectively rendering the data inaccessible. Given how widespread these anecdotes seemed online, speculation quickly mounted that the update itself was the culprit.
Microsoft, however, disputes the claim. In a statement, the company explained that extensive internal testing and telemetry reviews showed no evidence connecting the patch to SSD errors. The software giant said it has not observed any increased failure rates or corrupted volumes after the rollout of KB5063878. Still, Microsoft acknowledged the reports and confirmed that it is gathering additional details from affected users to assist in ongoing diagnostics.
The investigation has also extended to hardware vendors. Storage controller manufacturer Phison joined Microsoft in running thousands of hours of compatibility and stress tests to replicate the failures. According to both parties, more than 4,500 hours of testing produced no link between the update and the reported SSD issues, suggesting that the underlying problem could be unrelated to Windows. Microsoft has committed to keeping the situation under review should further evidence surface.
While the company insists that Windows 11 itself isn’t to blame, it has issued a precautionary guideline: users with SSDs more than 60 percent full should avoid transferring or writing very large files, as a safeguard until the cause of the failures is definitively identified. Though no direct fault has been found, the warning reflects Microsoft’s cautious approach as it works with partners to reassure users that their data remains safe.