diff --git a/README.md b/README.md
index fe91e8a..7408b21 100644
--- a/README.md
+++ b/README.md
@@ -400,6 +400,7 @@ awk -F '\t' '{print $2 "|" $1 "|" 0}' $FN >> ~/.zlua
 
 ## History
 
+- 1.4.3 (2019-02-08): fixed minor issues.
 - 1.4.2 (2019-02-06): you can disabled path validation by `$_ZL_NO_CHECK`, and use `z --purge` to clear bad paths manually.
 - 1.4.1 (2019-02-06): fzf tab-completion in bash (@[BarbUk](https://github.com/BarbUk)), fixed hang in fish shell (close [#29](https://github.com/skywind3000/z.lua/issues/29)).
 - 1.4.0 (2019-02-04): Ported to Power Shell ([@manhong2112](https://github.com/manhong2112))
diff --git a/z.lua b/z.lua
index c8558d5..d8a5b61 100755
--- a/z.lua
+++ b/z.lua
@@ -4,7 +4,7 @@
 -- z.lua - a cd command that learns, by skywind 2018, 2019
 -- Licensed under MIT license.
 --
--- Version 1.4.2, Last Modified: 2019/02/06 20:23
+-- Version 1.4.3, Last Modified: 2019/02/08 11:35
 --
 -- * 10x faster than fasd and autojump, 3x faster than z.sh
 -- * available for posix shells: bash, zsh, sh, ash, dash, busybox
@@ -422,6 +422,15 @@ end
 -- dir exists
 -----------------------------------------------------------------------
 function os.path.isdir(pathname)
+	if pathname == '/' then
+		return true
+	elseif windows then
+		if pathname == '\\' then
+			return true
+		elseif pathname:match('^%a:[/\\]$') then
+			return true
+		end
+	end
 	local name = pathname .. '/'
 	local ok, err, code = os.rename(name, name)
 	if not ok then