Internet Preventative Maintenance
Here are a few tips to help you prevent infection:
 

• Use an Internet Firewall
• Get computer updates and install security patches provided by your operating system vendor
• Protect yourself with up to date Anti-Virus Software
• E-mail attachments should never be opened unless one is 100% certain as to the nature of the attachment, who sent it, and why it was sent.
• Unsolicited e-mail attachments, regardless of who the sender is, should be treated as potential virus hazards. Proceed with caution.
• It is quite difficult for e-mail messages themselves to contain or be a virus; however attachments to messages may indeed contain viruses. Therefore, before opening any file you should first save it to disk and then run the virus detection program.
• Refrain, if possible, from downloading files from questionable Internet sites (for example, sites run by companies or individuals whose true identities are uncertain).
• Porn sites are notorious for Trojan Horses, viruses, malware and spyware.
• Scan all new files before opening them (Like files from a floppy, CD or from a download)
• Scan you computer on a regular basis
• Back-up important files on a regular basis

PC Preventive Maintenance Tips

Preventive maintenance is one of the most ignored aspects of PC ownership, in my opinion. Most people seem to think that the PC doesn't need preventive maintenance, and so you should just use it until it breaks, and then repair or replace it. These people generally find themselves repairing or replacing much sooner than those that take definite steps to avoid difficulties in the first place.
Here are some reasons why you should develop a preventive maintenance plan for your Computer:

• Preventive Maintenance Saves Money: I'm sure we've all heard the old adage "an ounce of prevention is worth a pound of cure". It's trite, but it is also true. Avoiding problems with your PC will save you money in the long run, compared with laying out cash for new components or repair jobs.
• Preventive Maintenance Saves Time: Saves time? How can taking two hours a month or whatever to perform maintenance save time? Simple: because it saves you the much bigger hassles of dealing with system failures and data loss. Most preventive maintenance procedures are quite simple compared to troubleshooting and repair procedures--now those can really eat up your time at a fantastic rate.
• Preventive Maintenance Helps Safeguard Your Data: For most people, the data on the hard disk is more important than the hardware that houses it. Taking steps to protect this data therefore makes sense, and that is what PM is all about.
• Preventive Maintenance Improves Performance: Some parts of your system will actually degrade in performance over time, and preventive maintenance will help to improve the speed of your system in these respects.