It's OK to digitally store important personal, household and family information on your home computer, provided you also store at least one digital duplicate -- much as you should have duplicates of hard copies of vital documents and materials.

The three most important rules of computing -- Back up. Back up. Back up. -- are apparently lost on most household because they fail to back up important data and learn the rules the hard way.

A national Harris Interactive survey of 597 computer users conducted for Imation, Corp., an Oakdale, MN-based removable data storage corporation, reveals nearly three out of five personal computer users have lost an electronic file they thought they had sufficiently stored and only one in four users frequently back up digital files, even when 85 percent of computer users say they are very concerned about losing important digital data.

Computer users' fears prompt most of them -- 82 percent -- to keep a hard copy of important documents they've also saved electronically.

Regular and frequent backups (especially after updating any important file) and current virus protection and firewall software should be de rigueur for home computer users just as it is for the corporate environment, according to Carnegie Mellon University's CERT Coordination Center (originally called the Computer Emergency Response Team), a major reporting center for Internet security problems.

Computer crashes, viral infections and hacking can destroy vital documents and maintaining important files on the home computer is as important as home maintenance.

"Computer crashes cost a lot more than they used to - our digital lives are so much a part of our daily lives," said Rusty Rosenberger, Imation director of business development.

"PC users keep finding new ways to fill up bigger and bigger hard drives -- with digital video, photos, music files and Internet downloads sitting alongside home finances, tax files, business records and school work. The survey shows that Americans love their data, but just don't manage it well. The answer is to get managing computer data on the 'to do list' -- regularly manage data and save important files to CDs or DVD discs."

Imation said most home computer uses only consider backing up data when it's too late -- after they've lost important data.

Thirty-seven percent of the survey's respondents admitted to backing up their files less than once per month and nine percent admitted they have never backed up their files. More than 22 percent said backing up information is on their to-do list, but they seldom do it.

Those who do back up generally take the right approach -- making duplicate copies. Among home computer users who backup information, 68 percent save the things most important to them in multiple places, the hard drive as well as removable media such as floppy disks (79 percent) compact disks (CDs, 58 percent). Floppy disks and hard drives are not as reliable as CDs and DVD (digital video disks), which can have a lifetime shelf life.

"Saving your data is one thing, but archiving it is another. Our survey shows that people understand that backing up is important if they want to protect their files and information -- but a significant number realize that they aren't getting to it often enough or at all, and remain concerned about loss," said Carla Pihowich, an Imation marketing manager.

"Optical media, such as CDs and DVDs, provide a permanence you just don't have with a hard drive," she added.

Fears of lost data preclude half of those surveyed from storing any household data on the computer, the survey said. Instead the home computer is more often used to store addresses and phone numbers, photographs, email archives, resumes and business documents.

Imation offers a series of files explaining backup and storage techniques and media.

Once you've downloaded them, back them up.