0x000003FD
ERROR_CHILD_MUST_BE_VOLATILE
Cannot create a stable subkey under a volatile parent key.
win32decimal 1021
Matched as: the code as given (hex)
Log a case with no specific solution
Source: System Error Codes (1000-1299) - Win32 apps · CC-BY-4.0 (MicrosoftDocs/sdk-api, repo license verified 2026-10-09) · retrieved 2026-10-09