diff --git a/dlls/itss/chm_lib.c b/dlls/itss/chm_lib.c
index 671fa8e3db5..be04ae5673a 100644
--- a/dlls/itss/chm_lib.c
+++ b/dlls/itss/chm_lib.c
@@ -807,21 +807,16 @@ struct chmFile *chm_openW(const WCHAR *filename)
         {
             newHandle->compression_enabled = 0;
         }
-
-        newHandle->window_size = ctlData.windowSize;
-        newHandle->reset_interval = ctlData.resetInterval;
-
+        else
+        {
+            newHandle->window_size = ctlData.windowSize;
+            newHandle->reset_interval = ctlData.resetInterval;
 /* Jed, Mon Jun 28: Experimentally, it appears that the reset block count */
 /*       must be multiplied by this formerly unknown ctrl data field in   */
 /*       order to decompress some files.                                  */
-#if 0
-        newHandle->reset_blkcount = newHandle->reset_interval /
-                    (newHandle->window_size / 2);
-#else
-        newHandle->reset_blkcount = newHandle->reset_interval    /
-                                    (newHandle->window_size / 2) *
-                                    ctlData.windowsPerReset;
-#endif
+            newHandle->reset_blkcount = newHandle->reset_interval / (newHandle->window_size / 2) *
+                                        ctlData.windowsPerReset;
+        }
     }
 
     return newHandle;