Always a better cure would be prevention. You could observe the following steps in order to avoid data loss situation.

An Anti Virus software should be used and keep it updated

Designed to protect you and your computer against malicious computer virus is an antivirus. There are virus infections that can cause your computer to crash while others can delete and also modify your data. Your Antivirus software should then be updated with the latest patch and signature files for maximum security.

To protect against power surges, use UPS

An uninterruptible power supply protects your computer and data during a power surge or failure. With the spare battery in the UPS, you will be given ample time to save your documents and shut down Windows properly so that you don't lose any files or damage any hardware components.

Keep your machine in a dry, shaded and dust-free area

Another thing you should avoid is leaving your computer near places where it is directly exposed to the rain, humidity, or the sun. Keep in mind that causing rusting and even damage to your hardware parts are such conditions.

You should never attempt to repair or open up your computer without assistance.

Without experience, you may damage the circuit boards, hardware components and worst of all, receive a nasty electric shock! That's why you should always consult with an expert.

Make sure that you don't over-tweak your system

Modifying your system registry or over working your hardware just to yield performance boost should be avoided unless you are absolutely sure of what you are doing. You don't wish to fry your computer.

At an off-site location, you should store your backups.

This helps to protect your backup from damage in case of a fire or disaster.

Avoid moving your computer when it is in operation

While working on a project, you definitely would not want your power cord to fall off and cause a data corruption as well as physical damage to your hard disk such as a head crash.

You should also avoid sharing access to your computer with strangers on the network.

If anyone on the network can access your files freely, then your computer data can be prone to theft and modification.

Disk maintenance should be practiced.

Clean up temporary files, unused files and defragment your hard disk from time to time. This helps to keep your hard disk on top form.

Read failure symptoms

When your hard disk starts producing funny noises and your system starts getting cranky, then you know it's time to start backing up all your data files.