(NewsUSA) - From digital photos to balancing the checkbook, it seems like most of our lives are wrapped up in our personal computers.

But when something goes awry - you open a document to begin making edits, the screen freezes and the document vanishes, or you open an e-mail and everything goes haywire - it's enough to make anyone hit the proverbial panic button.

However, more than 80 percent of online Americans haven't taken the appropriate computer protection measures and are at risk for online criminal activity or virus and spyware problems, according to the 2005 Online Safety Study. The study was developed by the National Cyber Security Alliance, a nonprofit organization promoting cybersecurity awareness and education (http://staysafeonline.org).

Here are some tips that can help keep your PC running smoothly, both inside and out:

• Never open e-mail messages or attachments from an unknown source.
• Keep your PC running at its speediest. Be sure to compress files and defragment your computer's hard drive once a month to avoid a sluggish machine.
• Sticky keys? It's time to clean. Every few weeks, use a computer keyboard cleaning kit to unclog dust buildup from beneath your keys.
• Your monitor needs a scrubdown from time to time. Use special cleaning wipes every few weeks to optimize your monitor's clarity.
• Properly shut down your computer every time you power down to avoid losing important documents.
• Don't invite intruders: Always keep your firewall enabled.
• Keep the bugs out: Always update your anti-virus software.
• Consider subscribing to a service such as Microsoft Windows Live OneCare. This all-in-one PC care service helps protect and maintain your computer with automatic updates of anti-virus software, routine maintenance such as disk defragmenting and cleaning out old files, as well as a backup and restore feature that makes it easy to help protect important documents, photos and music files.You can download Windows Live OneCare at http://onecare.live.com.