Error Message Text - Best Practices

Question

We are changing some of the text for our old, badly written error messages. What are some resources for best practices on writing good error messages (specifically for Windows XP/Vista).

Answer 1

Support for multilanguage applies for all kinds of messages, but tends to be forgotten in the case of error messages.

Answer 2

Try to figure out a way to write your software so it corrects the problem for them.

Answer 3

The ultimate best practice is to prevent the user from causing errors in the first place.

Don't tell users anything they don't care about; error code 5064 doesn't mean a thing to anyone. Don't tell them they did something wrong; disallow it in the first place. Don't blame them, especially not for mistakes your software made. Above all, when there is a problem, tell them how to fix it so they can move on and get some work done.

Answer 4

For security reasons, don't provide internal system information that the user does not need.
Trivial example: when failing to login, don't tell the user if the username is wrong or the password is wrong; this will only help the attacker to brute force the system. Instead, just say "Username/Password combination is invalid" or something like that.

Answer 5

1. Avoid identical error messages coming from different places; parametrize with file:line if possible, or use other context that lets you, the developer, uniquely identify where the error occurred.
2. Design the mechanism to allow easy localization, especially if it is a commercial product.
3. If the error messages are user-visible, make them complete, meaningful sentences that don't assume intimate knowledge of the code; remember, you're always too close to the problem -- the user is not. If possible, give the user guidance on how to proceed, who to contact, etc.
4. Every error should have a message if possible; if not, then try and make sure that all error-unwind paths eventually reach an error message that sheds light on what happened.
   
   I'm sure there will be other good answers here...

Answer 6

In terms of wording your error messages, I recommend referring to the following style guides for Windows applications:

• Windows user experience guidelines, and specifically the section on error messages here.
• Microsoft Manual of Style