diff --git a/contrib/pg_upgrade/file.c b/contrib/pg_upgrade/file.c
index 2aa48f049ad..fc78a06d8fb 100644
--- a/contrib/pg_upgrade/file.c
+++ b/contrib/pg_upgrade/file.c
@@ -41,7 +41,7 @@ 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 27dcd22a9b3..c32cfcae645 100644
--- a/contrib/pg_upgrade/util.c
+++ b/contrib/pg_upgrade/util.c
@@ -229,6 +229,8 @@ getErrorText(int errNum)
 {
 #ifdef WIN32
 	_dosmaperr(GetLastError());
+	/* _dosmaperr sets errno, so we copy errno here */
+	errNum = errno;
 #endif
 	return strdup(strerror(errNum));
 }