diff --git a/Utilities/cmtar/append.c b/Utilities/cmtar/append.c
index 4350745185..5ad3593ed2 100644
--- a/Utilities/cmtar/append.c
+++ b/Utilities/cmtar/append.c
@@ -231,7 +231,7 @@ tar_append_regfile(TAR *t, char *realname)
   int i, j;
   size_t size;
 
-  filefd = open(realname, O_RDONLY);
+  filefd = open(realname, O_RDONLY | O_BINARY);
   if (filefd == -1)
   {
 #ifdef DEBUG
diff --git a/Utilities/cmtar/libtar.c b/Utilities/cmtar/libtar.c
index 7454a5c03c..cdbe7a136d 100644
--- a/Utilities/cmtar/libtar.c
+++ b/Utilities/cmtar/libtar.c
@@ -15,7 +15,7 @@
 #include <stdio.h>
 #include <fcntl.h>
 #include <errno.h>
-#if !defined(_WIN32) || defined(__CYGWIN__)
+#if defined(_WIN32) && !defined(__CYGWIN__)
 #include <libtar/compat.h>
 #include <io.h>
 #else