Error message handling and it's importance

I have no idea about how far the test case will help in reviewing the error message. As, I do it in (follow) different approach, I just want to share how to handle the error message and it's importance.

Error message: 
 An error message in an information provided when some invalid data's are passed.

Error message is one of the important aspect in an application. Because when the user make some mistakes like providing an invalid details or any kind of irreverent request only the error message will speak to the user before the user contact the customer care. I think a proper message will reduce the number of customer care(employee) sometimes. The proper error message is important to tell the user about the problem. How to deliver an error message matters a lot. For example when the user has not entered any details at the mandatory field and by clicking on submit, if the message is shown like " Field cannot be empty or Please enter the " valid xxx" in the field" provided with the fields highlighted would be much better than just by showing (*) in red color.

How the message suppose to be shown?
1. Error message should be clear and easy to understand. So, try to give it in the normal words.
2. Some of the modules like application form, the error message can be shown by highlighting the fields in red color or at the place where the user could view it preferably at the top of the page.
3. Don't  try to provide it in a essay format. Always try to show it as simple and short".
4. Check for grammar
5. Spell check
6 .Show it in a separate dialog box or in that page itself (it depends on application and the space availability in the page)
7.If the error message is like (404 error), then tell the user why such error was occurred and what is that error.
8. If it is internal server error(500 error) then the user should know it happens just because of the server.So,  if possible provide details about the 500 error.

How the message should not be shown?
1. For some of the message, the message is shown like " the stack over flow with some code.  This goes useless and the  user might get irritated.
2. Showing it at the bottom of the page where the probability is less for the user to view.
3. Providing more than one dialog box
4. Confusing content like
    Are you sure you don't want to remove? and the options are  (yes and No)
5. Not showing a message at all even after making some invalid attempt.But still remains on the same page.

I have come across some of the application, where the error message is shown at the bottom of the page and is not view-able by the user .The user could see such message by scrolling the page. This would cause a trouble to the user. Because sometime the user might not aware of such issue and try for few more attempt and finally there is a chance to come out of the site.

"A good error message will create good impression to the user". Some good way to start a message like saying  sorry,  please,etc. will tell the user that they are more valuable.

My Contact Information:

Email id: ktg.pradeep@gmail.com
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