diff --git a/xtoskrnl/ke/amd64/kthread.c b/xtoskrnl/ke/amd64/kthread.c
index 7104b57..096d7d6 100644
--- a/xtoskrnl/ke/amd64/kthread.c
+++ b/xtoskrnl/ke/amd64/kthread.c
@@ -50,6 +50,9 @@ KepInitializeThreadContext(IN PKTHREAD Thread,
     /* Check if context provided for this thread */
     if(ContextRecord)
     {
+        /* User mode thread needs further initialization, this is not completed */
+        UNIMPLEMENTED;
+
         /* Fill exception and trap frames with zeroes */
         RtlZeroMemory(&ThreadFrame->ExceptionFrame, sizeof(KEXCEPTION_FRAME));
         RtlZeroMemory(&ThreadFrame->TrapFrame, sizeof(KTRAP_FRAME));
diff --git a/xtoskrnl/ke/i686/kthread.c b/xtoskrnl/ke/i686/kthread.c
index 95b003a..77bd8d5 100644
--- a/xtoskrnl/ke/i686/kthread.c
+++ b/xtoskrnl/ke/i686/kthread.c
@@ -51,6 +51,9 @@ KepInitializeThreadContext(IN PKTHREAD Thread,
     /* Check if context provided for this thread */
     if(ContextRecord)
     {
+        /* User mode thread needs further initialization, this is not completed */
+        UNIMPLEMENTED;
+
         /* Fill trap frame with zeroes */
         RtlZeroMemory(&ThreadFrame->TrapFrame, sizeof(KTRAP_FRAME));