diff --git a/reactos/win32ss/drivers/videoprt/int10.c b/reactos/win32ss/drivers/videoprt/int10.c
index b6a5eb93afe..71c377c44a1 100644
--- a/reactos/win32ss/drivers/videoprt/int10.c
+++ b/reactos/win32ss/drivers/videoprt/int10.c
@@ -135,6 +135,15 @@ IntInitializeVideoAddressSpace(VOID)
     /* Return success */
     return STATUS_SUCCESS;
 }
+#else
+NTSTATUS
+NTAPI
+IntInitializeVideoAddressSpace(VOID)
+{
+    UNIMPLEMENTED;
+    NT_ASSERT(FALSE);
+    return STATUS_NOT_IMPLEMENTED;
+}
 #endif
 
 #if defined(_M_IX86)