diff --git a/sdk/xtdk/ketypes.h b/sdk/xtdk/ketypes.h
index 6331433..0e8a3fc 100644
--- a/sdk/xtdk/ketypes.h
+++ b/sdk/xtdk/ketypes.h
@@ -313,14 +313,6 @@ typedef struct _EXCEPTION_RECORD
     ULONG_PTR ExceptionInformation[EXCEPTION_MAXIMUM_PARAMETERS];
 } EXCEPTION_RECORD, *PEXCEPTION_RECORD;
 
-/* Group affinity structure definition */
-typedef struct _GROUP_AFFINITY
-{
-    KAFFINITY Mask;
-    USHORT Group;
-    USHORT Reserved[3];
-} GROUP_AFFINITY, *PGROUP_AFFINITY;
-
 /* Extended affinity structure definition */
 typedef struct _KAFFINITY_MAP
 {
@@ -611,9 +603,9 @@ typedef struct _KTHREAD
     CHAR PreviousMode;
     UCHAR ResourceIndex;
     UCHAR DisableBoost;
-    GROUP_AFFINITY UserAffinity;
+    KAFFINITY_MAP UserAffinity;
     PKPROCESS Process;
-    GROUP_AFFINITY Affinity;
+    KAFFINITY_MAP Affinity;
     PVOID ServiceTable;
     PKAPC_STATE ApcStatePointer[2];
     KAPC_STATE SavedApcState;
diff --git a/sdk/xtdk/xtstruct.h b/sdk/xtdk/xtstruct.h
index 9da9e1d..76df5a8 100644
--- a/sdk/xtdk/xtstruct.h
+++ b/sdk/xtdk/xtstruct.h
@@ -248,7 +248,6 @@ typedef struct _EXCEPTION_REGISTRATION_RECORD EXCEPTION_REGISTRATION_RECORD, *PE
 typedef struct _FIRMWARE_INFORMATION_BLOCK FIRMWARE_INFORMATION_BLOCK, *PFIRMWARE_INFORMATION_BLOCK;
 typedef struct _FLOAT128 FLOAT128, *PFLOAT128;
 typedef struct _GENERIC_ADDRESS GENERIC_ADDRESS, *PGENERIC_ADDRESS;
-typedef struct _GROUP_AFFINITY GROUP_AFFINITY, *PGROUP_AFFINITY;
 typedef struct _GUID GUID, *PGUID;
 typedef struct _HL_FRAMEBUFFER_DATA HL_FRAMEBUFFER_DATA, *PHL_FRAMEBUFFER_DATA;
 typedef struct _HL_SCROLL_REGION_DATA HL_SCROLL_REGION_DATA, *PHL_SCROLL_REGION_DATA;
diff --git a/xtoskrnl/ke/amd64/krnlinit.cc b/xtoskrnl/ke/amd64/krnlinit.cc
index 01b760b..cc06462 100644
--- a/xtoskrnl/ke/amd64/krnlinit.cc
+++ b/xtoskrnl/ke/amd64/krnlinit.cc
@@ -118,8 +118,9 @@ KE::KernelInit::BootstrapKernel(VOID)
     CurrentThread->NextProcessor = Prcb->CpuNumber;
     CurrentThread->Priority = THREAD_HIGH_PRIORITY;
     CurrentThread->State = Running;
-    CurrentThread->Affinity.Mask = (KAFFINITY)1 << Prcb->CpuNumber;
-    CurrentThread->Affinity.Group = 0;
+    CurrentThread->Affinity.Count = 1;
+    CurrentThread->Affinity.Size = 1;
+    CurrentThread->Affinity.Bitmap[0] = (KAFFINITY)1 << Prcb->CpuNumber;
     CurrentThread->WaitRunLevel = DISPATCH_LEVEL;
     CurrentProcess->ActiveProcessors.Bitmap[0] |= (KAFFINITY)1 << Prcb->CpuNumber;
 
diff --git a/xtoskrnl/ke/i686/krnlinit.cc b/xtoskrnl/ke/i686/krnlinit.cc
index 94533d0..a87da8a 100644
--- a/xtoskrnl/ke/i686/krnlinit.cc
+++ b/xtoskrnl/ke/i686/krnlinit.cc
@@ -118,8 +118,9 @@ KE::KernelInit::BootstrapKernel(VOID)
     CurrentThread->NextProcessor = Prcb->CpuNumber;
     CurrentThread->Priority = THREAD_HIGH_PRIORITY;
     CurrentThread->State = Running;
-    CurrentThread->Affinity.Mask = (KAFFINITY)1 << Prcb->CpuNumber;
-    CurrentThread->Affinity.Group = 0;
+    CurrentThread->Affinity.Count = 1;
+    CurrentThread->Affinity.Size = 1;
+    CurrentThread->Affinity.Bitmap[0] = (KAFFINITY)1 << Prcb->CpuNumber;
     CurrentThread->WaitRunLevel = DISPATCH_LEVEL;
     CurrentProcess->ActiveProcessors.Bitmap[0] |= (KAFFINITY)1 << Prcb->CpuNumber;