diff --git a/README.rdoc b/README.rdoc
index 309bb68..780db2b 100644
--- a/README.rdoc
+++ b/README.rdoc
@@ -26,7 +26,7 @@ Add the following to your application's "shard.yml":
  dependencies:
    maildir:
      github: crystallabs/maildir.cr
-     version 5.0.1
+     version 6.0.0
 
 And run "shards install".
 
diff --git a/shard.yml b/shard.yml
index efee948..a4192b7 100644
--- a/shard.yml
+++ b/shard.yml
@@ -1,10 +1,10 @@
 name: maildir
-version: 5.0.1
+version: 6.0.0
 
 authors:
   - Davor Ocelic <docelic@crystallabs.io>
 
-crystal: 0.32.0
+crystal: 0.34.0
 
 license: MIT
 
diff --git a/src/message.cr b/src/message.cr
index e0db994..4f3f520 100644
--- a/src/message.cr
+++ b/src/message.cr
@@ -207,18 +207,14 @@ class Maildir
     # false, otherwise reraises Errno::ENOENT
     protected def guard(reraise = false, &block)
         yield
-      rescue e : Errno
-        if e.errno== Errno::ENOENT
-          if ok= @old_key
-            # Restore ourselves to the old state
-            parse_key(ok)
-          end
+      rescue e : File::NotFoundError
+        if ok= @old_key
+          # Restore ourselves to the old state
+          parse_key(ok)
+        end
 
         #  # Don't allow further modifications
         #  #freeze
-        else
-          raise(Exception.new)
-        end
 
         reraise ? raise(Exception.new) : false
     end
diff --git a/src/version.cr b/src/version.cr
index b425356..bb8c574 100644
--- a/src/version.cr
+++ b/src/version.cr
@@ -1,3 +1,3 @@
 class Maildir
-  VERSION = "5.0.1"
+  VERSION = "6.0.0"
 end