diff --git a/Shelly.hs b/Shelly.hs
--- a/Shelly.hs
+++ b/Shelly.hs
@@ -693,8 +693,11 @@
 
 instance Show RunFailed where
   show (RunFailed exe args code errs) =
-    "error running: " ++ LT.unpack (show_command exe args) ++
-      "\nexit status: " ++ show code ++ "\nstderr: " ++ LT.unpack errs
+    let codeMsg = case code of
+          127 -> ". exit code 127 usually means the command does not exist (in the PATH)"
+          _ -> ""
+    in "error running: " ++ LT.unpack (show_command exe args) ++
+         "\nexit status: " ++ show code ++ codeMsg ++ "\nstderr: " ++ LT.unpack errs
 
 instance Exception RunFailed
 
diff --git a/shelly.cabal b/shelly.cabal
--- a/shelly.cabal
+++ b/shelly.cabal
@@ -1,6 +1,6 @@
 Name:       shelly
 
-Version:     0.9.5
+Version:     0.9.5.1
 Synopsis:    shell-like (systems) programming in Haskell
 
 Description: Shelly provides a single module for convenient