Microsoft reports it has found no evidence that the August security update for Windows 11 24H2 (KB5063878) is causing SSD or HDD failures, despite a wave of user posts linking the patch to drive dropouts and potential data loss. According to the company, internal telemetry and controlled test runs did not reveal disk anomalies after installation, though the collection of field reports continues.
Microsoft: telemetry shows no correlation with KB5063878
Microsoft engineers state they were unable to reproduce storage failures on current builds, including in collaboration with storage manufacturers. “After a thorough investigation, Microsoft has not identified a link between the August 2025 security update and reports of disk issues,” the company said in an official comment. Microsoft will maintain heightened monitoring and asks affected users to submit detailed incident logs.
Joint testing and ongoing monitoring
Extended lab evaluations and telemetry analysis have not shown file system degradation, data loss, or disappearing drives that can be conclusively tied to KB5063878 on Windows 11 24H2. Microsoft is continuing to analyze community submissions and advises users to include event logs, dump files, and firmware versions when reporting.
User reports: NVMe dropouts during heavy write workloads
Roughly two weeks prior, researchers and end users began associating drive outages with KB5063878 and the preview update KB5062660 for Windows 11 24H2. Several reports describe drives going offline during sustained writes—such as mass file copies or large game updates—with a subset of devices reappearing after reboot while others remained inaccessible.
Community-noted models and controllers
User posts referenced models such as SanDisk Extreme Pro, Corsair Force MP600, Maxio SSD, KIOXIA EXCERIA PLUS G4, and KIOXIA M.2 SSD, often on Phison PS5012-E12 or InnoGrit controllers. Multiple reports also note that DRAM-less SSDs appear more prone to failures under moderate-to-high write queue depths.
Vendor responses: Phison disputes “affected controller” list, shares test data
As highlighted by Tom’s Hardware, a purported list of “affected” Phison controllers circulated online shortly after the first complaints. Phison says the document is a forgery and unrelated to the company, adding that it intends to pursue legal action against those spreading misinformation.
Phison reports conducting more than 4,500 hours of testing without reproducing the issue. The company recommends installing NVMe heatsinks for systems under high sustained write loads to reduce thermal throttling risk—standard practice to improve stability during intensive operations.
Technical analysis: why SSDs can fail under heavy I/O
Drive dropouts under heavy writes are frequently attributed to a combination of factors rather than a single OS update. Common contributors include heat-induced thermal throttling, controller firmware edge cases, exhaustion of SLC cache, write amplification during large transfers, NVMe command timeouts, and power-saving modes such as APST/ASPM. Driver stack interactions (including the Windows stornvme driver) and system-specific chipset behaviors can also play a role. DRAM-less designs are inherently more sensitive to fragmented I/O and deep write queues.
Security updates can indirectly raise storage load—through antimalware scans, re-indexing, and patch installation—surfacing pre-existing hardware/firmware constraints. However, without reproducibility and corroborating telemetry, attributing failures to a specific patch is not methodologically sound.
Practical guidance for IT and power users
Do not defer critical updates; instead, roll them out in phases. Use pilot rings, monitor system metrics, then proceed to broad deployment. Verify that SSD firmware, chipset drivers, and NVMe drivers are current, and ensure adequate airflow and heatsinking for M.2 devices.
Continuously monitor SMART attributes (e.g., reallocated sectors, media errors, temperature) and review Windows Event Viewer for storage warnings and NVMe timeouts. For high I/O environments, plan heatsink installation, maintain reliable backups, and avoid overlapping large write tasks during major updates. If issues recur, collect detailed diagnostics (kernel/user-mode dumps, reliability reports, NVMe logs, firmware versions) and submit them to Microsoft and the drive vendor.
The situation around KB5063878 underscores the value of disciplined patch management and transparent telemetry. As of publication, neither Microsoft nor storage OEMs have confirmed a causal link between the update and disk failures. Continue to apply security updates using staged deployment and operational best practices to minimize risk while contributing actionable diagnostics to vendors when anomalies occur.
