diff --git a/contrib/pg_upgrade/file.c b/contrib/pg_upgrade/file.c
index 40463c61369..a1b0176590a 100644
--- a/contrib/pg_upgrade/file.c
+++ b/contrib/pg_upgrade/file.c
@@ -37,7 +37,7 @@ copyAndUpdateFile(pageCnvCtx *pageConverter,
 #ifndef WIN32
 		if (copy_file(src, dst, force) == -1)
 #else
-		if (CopyFile(src, dst, force) == 0)
+		if (CopyFile(src, dst, !force) == 0)
 #endif
 			return getErrorText(errno);
 		else
diff --git a/contrib/pg_upgrade/util.c b/contrib/pg_upgrade/util.c
index c0d9deebca4..d323045deb3 100644
--- a/contrib/pg_upgrade/util.c
+++ b/contrib/pg_upgrade/util.c
@@ -253,6 +253,8 @@ getErrorText(int errNum)
 {
 #ifdef WIN32
 	_dosmaperr(GetLastError());
+	/* _dosmaperr sets errno, so we copy errno here */
+	errNum = errno;
 #endif
 	return pg_strdup(strerror(errNum));
 }