According to Wikipedia, nearly 9% of computer users around the world are still using Windows Vista as of April 2012. For that reason, we’re going to teach you a few of the best ways to fix your Windows Vista computer for free.

Disable UAC

The User Account Control is ridiculously restrictive. Any time you want to change one of Vista’s most basic settings – like the time on the clock – the UAC pops up and asks you if you’re sure you want to do that.
If you’re like most people, then you don’t really need this prompt when you’re just trying to change the time of day. In fact, leaving the UAC on can be dangerous for your computer because users end up ignoring its advice.
To disable the UAC, go to Start, then, Control Panel, then User Accounts and then select Turn User Account Control on or off. Then, uncheck Use User Account Control (UAC) to protect your computer on the next screen and select OK. All gone!

Startup Repair

If Windows Vista is experiencing any sort of startup problems, then it’s important to repair your installation as soon as possible. Fortunately, repairing a Vista installation is probably easier than you think.
First, put your Windows Vista DVD into your disk drive. Then, restart your computer and wait for an installation logo to appear (if it doesn’t appear, then you may have to restart your computer and press F8 when the Microsoft logo appears).
Navigate through the installation screen and look for a button that says Repair your computer. Let the DVD go to work. Ideally, the disk will start to repair your installation and will fix the areas of your operating system that have become missing or corrupted.
Sometimes, Vista startup repair won’t work properly. You may get an error like Windows cannot repair this computer automatically. Fortunately, there are other options available. Complete PC restore and the Memory Diagnostic Tool are particularly useful.

Clean your Vista registry

Windows Registry problems are the cause of all sorts of different issues within Vista. Since the registry controls the configuration data within programs, one misplaced line of code can have reverberating effects across the rest of your PC.
To avoid having registry problems wreck your system’s performance and security, try running a free scan with PC Cleaner Pro. Along with scanning your registry for serious errors, PC Cleaner Pro 2012 identifies and removes thousands of other system errors as well. This is what makes it such a fantastic tool.
PC Cleaner Pro also fixes other common problems that affect the Vista operating system. It eliminates malware at the source and cracks down on PC clutter. By speeding up your PC and fixing hundreds of trouble spots, PC Cleaner Pro makes its value known immediately.