diff --git a/lib/zip_source_win32a.c b/lib/zip_source_win32a.c
index bb3ebaa..0b79e63 100644
--- a/lib/zip_source_win32a.c
+++ b/lib/zip_source_win32a.c
@@ -84,7 +84,7 @@
 static HANDLE
 _win32_open_a(_zip_source_win32_read_file_t *ctx)
 {
-    return CreateFileA(ctx->fname, GENERIC_READ, FILE_SHARE_READ, NULL, OPEN_EXISTING, FILE_ATTRIBUTE_NORMAL, NULL);
+    return CreateFileA(ctx->fname, GENERIC_READ, FILE_SHARE_READ | FILE_SHARE_WRITE, NULL, OPEN_EXISTING, FILE_ATTRIBUTE_NORMAL, NULL);
 }
 
 
diff --git a/lib/zip_source_win32w.c b/lib/zip_source_win32w.c
index d18b432..40d34fb 100644
--- a/lib/zip_source_win32w.c
+++ b/lib/zip_source_win32w.c
@@ -84,7 +84,7 @@
 static HANDLE
 _win32_open_w(_zip_source_win32_read_file_t *ctx)
 {
-    return CreateFileW(ctx->fname, GENERIC_READ, FILE_SHARE_READ, NULL, OPEN_EXISTING, FILE_ATTRIBUTE_NORMAL, NULL);
+    return CreateFileW(ctx->fname, GENERIC_READ, FILE_SHARE_READ | FILE_SHARE_WRITE, NULL, OPEN_EXISTING, FILE_ATTRIBUTE_NORMAL, NULL);
 }