An IBM information storage expert has said that CD-Rs and DVD±Rs typically last only two to five years. Is that true?

Walter Sekula, Greensburg, Pennsylvania

Kurt Gerecke of IBM Deutschland GmbH caused quite a stir in January when he stated that "unlike pressed original CDs, burned CDs have a relatively short life span of between two to five years, depending on the quality of the CD." Since then, I've seen his estimate quoted as established fact.

What I haven't seen is real-world evidence. I have yet to receive a single Answer Line letter about an aged disc. I checked with Ontrack and DriveSavers, the two leading data recovery services, and neither reports that age is causing CD-R failures. When I tested some of the oldest CD-Rs I own, I found no errors on them (and most of those discs were the cheapest I could buy at the time). CD-Rs have been common for much longer than five years; if their shelf life was that short, we'd have known it long ago.

But that doesn't mean these discs will last forever, or even as long as the pressed CDs and DVDs on which we buy music, movies, and software. The jury is still out on whether the discs will last for years or decades. However, you can increase the longevity of your optical media.

First, use high-quality discs, preferably ones made with stable dyes and gold backings (see Figure 1). KMP Media markets such discs under the Kodak name; Delkin Devices sells a similar line. Make multiple copies of important data, and store them in separate locations (preferably in different cities).

To write on the label side of the disc, use a nonsoluble, felt-tip marker designed specifically for writing on CDs and DVDs. Store discs upright, and in good cases intended for that purpose. Keep them away from heat, light, and moisture.

Check the discs every few years by copying files off of them to make sure they're still readable. In addition to storing your archival data on CDs or DVDs, keep it on your hard drive and back it up regularly.