<p>I am looking for a good way to consistently test my web applications from the end users point of view. I have all kinds of ways to check to make sure my code is working behind the scenes. I can't count the number of times that I make a change to a piece of code, test it and it works fine and then deploy it only to have it blow up somewhere else weeks later. I have by that time forgotten the change I made that caused it to blow up. I need something that I can run every time I make a change to assure me I did not break something somewhere else.</p>

<p>It needs to be able to input correct and incorrect entries so that client side validation can be tested also.</p>

<p>Thank you,</p>

<p>Scott and the Dev Team</p>

I thin you need to investigate
Selenium
. We use it to do automated UI testing throughout our solution, and it is cross browser and cross platform.
You can use the
Selenium IDE
to record a walkthrough of your web application, and then you can either run it in the browser, or export it to various languages such as C#, and run it using NUnit. I find this is the easiest approach because I can create the basic walkthrough and then modify the code to use inputs from a file/database in order to create multiple scenarios.