The SYSTEM_SET_TIME_ADJUST_INFORMATION structure is expected as input to ZwSetSystemInformation or NtSetSystemInformation when given the information class SystemTimeAdjustmentInformation (0x1C).

Documentation Status

The SYSTEM_SET_TIME_ADJUST_INFORMATION structure is not documented.

Microsoft does publish the practical equivalent of a C-language definition as type information in public symbol files, though not for the kernel, where the structure is prepared, nor even for low-level user-mode DLLs that interpret the structure, but for various higher-level user-mode DLLs such as URLMON.DLL and only then starting with version 6.2.

Two earlier disclosures of type information are known, though not in symbol files but in statically linked libraries: GDISRVL.LIB from the Device Driver Kit (DDK) for Windows NT 3.51; and SHELL32.LIB from the DDK for Windows NT 4.0.


The SYSTEM_SET_TIME_ADJUST_INFORMATION is 0x08 bytes in both 32-bit and 64-bit Windows.

Offset Definition
ULONG TimeAdjustment;