Here are some constants from winnt.h i think you ask for // // Used to represent information related to a thread impersonation // typedef struct _SE_IMPERSONATION_STATE { PACCESS_TOKEN Token; BOOLEAN CopyOnOpen; BOOLEAN EffectiveOnly; SECURITY_IMPERSONATION_LEVEL Level; } SE_IMPERSONATION_STATE, *PSE_IMPERSONATION_STATE; typedef DWORD SECURITY_INFORMATION, *PSECURITY_INFORMATION; #define OWNER_SECURITY_INFORMATION (0X00000001L) #define GROUP_SECURITY_INFORMATION (0X00000002L) #define DACL_SECURITY_INFORMATION (0X00000004L) #define SACL_SECURITY_INFORMATION (0X00000008L) Winfried