Error safely ejecting external drives

Title:

UASP external drives no longer power down after eject on Windows 11 24H2 (26100.7171)

Category:

Devices and Drivers → USB → External Storage

Description:

Starting between the October 2025 cumulative update (where it still worked) and early November, all UASP external SSDs/HDDs fail to fully eject or power down after “Safe to Remove Hardware.”
Flash drives (Bulk-Only / USBStor) still eject correctly.

Environment:

Laptop: ASUS K6500ZC (Intel i7-12650H, BIOS 303, Intel VMD enabled)

OS: Windows 11 24H2 Build 26100.7171 (clean install from MCT ISO)

Drivers:
• Intel RST VMD Controller 467F + 09AB
• Intel RST 20.2.6.1025.2
• uaspstor.sys 10.0.26100.1882

Affected devices: all external SSDs/HDDs using UASP (“SCSI UAS Mass Storage Device”)

Unaffected devices: standard flash drives using USBStor.sys

Reproduction:

Connect any UASP external drive.

Wait until fully enumerated.

Use “Safely Remove Hardware.”
→ Message: “Windows is using the device” or, if it ejects, the device remains powered.

Plugging it back repeats the issue almost every time.

Notes:

Issue persists after clean installs, driver reinstalls, EC power drains, BIOS resets.

Other Intel VMD systems (Dell Inspiron, Lenovo Legion, ASUS VivoBook) reportedly show the same behavior on 26100+ builds.

Strongly points to regression in UASP/VMD driver interaction since 26100.1882.

Please escalate to USB & Storage team for investigation of uaspstor.sys behavior under VMD controllers.

Expected behavior:
After “Safe to Remove,” drive should flush cache, power down, and detach as in pre-Nov 2025 builds.