diff --git a/test/old/testdir/shared.vim b/test/old/testdir/shared.vim
index cefca1c2e6..205847fc0e 100644
--- a/test/old/testdir/shared.vim
+++ b/test/old/testdir/shared.vim
@@ -82,8 +82,8 @@ endfunc
 " Read the port number from the Xportnr file.
 func GetPort()
   let l = []
-  " with 200 it sometimes failed
-  for i in range(400)
+  " with 200 it sometimes failed, with 400 is rarily failed
+  for i in range(600)
     try
       let l = readfile("Xportnr")
     catch