diff --git a/src/uicommon.ml b/src/uicommon.ml
index 6dd6a4067..a428dfc05 100644
--- a/src/uicommon.ml
+++ b/src/uicommon.ml
@@ -353,10 +353,10 @@ let reconItem2string oldPath theRI status =
 let exn2string e =
   match e with
      Sys.Break      -> "Terminated!"
-   | Util.Fatal(s)  -> Printf.sprintf "Fatal error: %s" s
-   | Util.Transient(s) -> Printf.sprintf "Error: %s" s
+   | Util.Fatal s   -> s
+   | Util.Transient s -> s
    | Unix.Unix_error (err, fun_name, arg) ->
-       Printf.sprintf "Uncaught unix error: %s failed%s: %s%s\n%s"
+       Printf.sprintf "Uncaught unix error (please report a bug): %s failed%s: %s%s\n%s"
          fun_name
          (if String.length arg > 0 then Format.sprintf " on \"%s\"" arg else "")
          (Unix.error_message err)
@@ -365,8 +365,9 @@ let exn2string e =
           | _                  -> "")
          (Printexc.get_backtrace ())
    | Invalid_argument s ->
-       Printf.sprintf "Invalid argument: %s\n%s" s (Printexc.get_backtrace ())
-   | other -> Printf.sprintf "Uncaught exception %s\n%s"
+       Printf.sprintf "Invalid argument (please report a bug): %s\n%s"
+         s (Printexc.get_backtrace ())
+   | other -> Printf.sprintf "Uncaught exception (please report a bug): %s\n%s"
        (Printexc.to_string other) (Printexc.get_backtrace ())
 
 (* precondition: uc = File (Updates(_, ..) on both sides *)
diff --git a/src/uigtk3.ml b/src/uigtk3.ml
index 23c5ba2c0..15c65bad3 100644
--- a/src/uigtk3.ml
+++ b/src/uigtk3.ml
@@ -299,7 +299,7 @@ let primaryText msg =
    chosen, false if the second button is chosen. *)
 let twoBox ?(kind=`DIALOG_WARNING) ~parent ~title ~astock ~bstock message =
   let t =
-    GWindow.dialog ~parent ~border_width:6 ~modal:true
+    GWindow.dialog ~parent ~title ~border_width:6 ~modal:true
       ~resizable:false () in
   t#vbox#set_spacing 12;
   let h1 = GPack.hbox ~border_width:6 ~spacing:12 ~packing:t#vbox#pack () in
@@ -345,7 +345,7 @@ let warnBox ~parent title message =
   if Prefs.read Globals.batch then begin
     (* In batch mode, just pop up a window and go ahead *)
     let t =
-      GWindow.dialog ~parent
+      GWindow.dialog ~parent ~title
         ~border_width:6 ~modal:true ~resizable:false () in
     t#vbox#set_spacing 12;
     let h1 = GPack.hbox ~border_width:6 ~spacing:12 ~packing:t#vbox#pack () in
@@ -685,11 +685,11 @@ let gui_safe_eprintf fmt =
     if System.has_stderr ~info:s then Printf.eprintf "%s%!" s) fmt
 
 let fatalError ?(quit=false) message =
+  let title = if quit then "Fatal error" else "Error" in
   let () =
     Trace.sendLogMsgsToStderr := false; (* We don't know if stderr is available *)
-    try Trace.log (message ^ "\n")
+    try Trace.log (title ^ ": " ^ message ^ "\n")
     with Util.Fatal _ -> () in (* Can't allow fatal errors in fatal error handler *)
-  let title = "Fatal error" in
   let toplevelWindow =
     try Some (toplevelWindow ())
     with Util.Fatal err ->
@@ -1650,9 +1650,9 @@ let createProfile parent =
       if React.state fat then Printf.fprintf ch "fat = true\n";
       close_out ch);
       profileName := Some (React.state name)
-    with Sys_error _ as e ->
+    with Sys_error errmsg ->
       okBox ~parent:assistant ~typ:`ERROR ~title:"Could not save profile"
-        ~message:(Uicommon.exn2string e)
+        ~message:("Error when saving profile: " ^ errmsg)
     end;
     assistant#destroy ();
   in
@@ -2393,9 +2393,9 @@ let editProfile parent name =
              false);
         close_out ch);
         setModified false
-      with Sys_error _ as e ->
+      with Sys_error errmsg ->
         okBox ~parent:t ~typ:`ERROR ~title:"Could not save profile"
-          ~message:(Uicommon.exn2string e)
+          ~message:("Error when saving profile: " ^ errmsg)
     end
   in
   let applyButton =
diff --git a/src/uitext.ml b/src/uitext.ml
index a2aaccf97..000104c7d 100644
--- a/src/uitext.ml
+++ b/src/uitext.ml
@@ -1585,7 +1585,10 @@ let handleException e =
   alwaysDisplay "\n";
   Util.set_infos "";
   restoreTerminal();
-  let msg = Uicommon.exn2string e in
+  let lbl =
+    if e = Sys.Break then ""
+    else "Error: " in
+  let msg = lbl ^ Uicommon.exn2string e in
   let () =
     try Trace.log (msg ^ "\n")
     with Util.Fatal _ -> () in (* Can't allow fatal errors in fatal error handler *)