Windows 11 25H2 blocked on some WD and SanDisk NVMe SSDs

Users are reporting trouble installing the Windows 11 25H2 update on some Western Digital and SanDisk NVMe SSDs. When attempting to move up from version 24H2, the system displays an incompatibility warning for the drives and blocks the installation. Analysts link the failure to firmware mishandling of the Host Memory Buffer (HMB) feature, a glitch that can trigger critical errors and even blue screens. Taken together, the signs point to firmware rather than the OS as the weak link.

Compatibility issues have been confirmed for the WD_BLACK SN770 NVMe SSD 2TB, WD_BLACK SN770M NVMe SSD 2TB, WD Blue SN580 NVMe SSD 2TB, WD Blue SN5000 NVMe SSD 2TB, and the SanDisk Extreme M.2 NVMe SSD 2TB. All of them rely on HMB instead of onboard DRAM, and in this setup a defective microcode build can clash with the system. That makes clean firmware especially important.

A similar situation was already observed with Windows 11 24H2, after which Western Digital and SanDisk released firmware updates to fix the failures. Experts advise installing the latest firmware from the manufacturers’ support pages before moving to Windows 11 25H2 to avoid upgrade issues. Given that recent history, holding off on the OS update until after a firmware refresh looks like the sensible move.