Hey guys, just making this post as a guide to help anybody who's having the problem I had earlier today. When I launched minecraft, I got an error that said "You need the Java Runtime Environment 1.5.0" In order to solve this problem. It seems like there are a few different solutions for different people, so this guide will attempt to cover all the bases. This guide is for Windows, and written specifically for Windows 7. However, I've tried to add links for information on how do to the same thing on other systems. Also, you've probably already tried a few things, but please don't skip any steps just because you've done them before. It'll be better for both of us. But mostly you.
As much as I didn't really want to, I wrote up this guide. So, if it works for you, please just drop a note saying so! It'll help other people know that this is a good solution.
So, without further ado, How To Fix the "Java Runtime Environment 1.5.0" Startup Error
Step 1: Uninstall All Copies of Java
Go to the Start Menu
Type "Add or remove programs" and select the matching result (Or, Control Panel -> Programs and Features)
Remove all versions of Java
Step 2: Save this link. Restart your computer. Yes, really.
Actually do this.
Step 3: Install the latest version of Java. (Version 7 update 21 as of 4/30/13)