How long will data last?

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By Catherine Holland By Catherine Holland

Q. I hear people talking occasionally about a computer crash, but I'm embarrassed to say that I don't know what that means. What is a crash?

A. No need to ever be embarrassed about any question here in Mr. Modemville. All questions are welcome. Generically, a computer crash is a hardware or software problem that causes information to be lost or the device (computer, printer, etc.) to malfunction. Sometimes a crash can cause permanent damage to a computer; other times it manifests itself as a “freeze,” where nothing viewed on screen moves. Some crashes can be resolved by restarting the computer; at the other extreme, a reinstallation of Windows or a given program is required. Windows crashes are sometimes accompanied by what is referred to as the Blue Screen of Death or BSOD.

Q. I use Thunderbird for my email, thanks to your recommendation and I really like it. What I can't figure out is how to create a mail filter. Can you help me? Thanks. Mr. M.

A. To create message filters with Thunderbird (, click Tools > Message Filters > New. Provide a name for your filter, then follow the on-screen instructions to create a filter for incoming messages that match any or all of the conditions you specify.

In the Perform These Actions section, you will instruct Thunderbird what to do with any message that meets your filtering criteria. For example, you might want to flag a message based on its sender or Subject line, move it to a specific folder, or delete it upon arrival. When you’ve made your selections, click the OK button and you'll be good to go.

Q. How long will backed-up data last on my CD-ROM?

A. As with any back-up medium (CD/DVD, flash drive, stone tablet, etc.) the shelf life of saved data is an important consideration. Kodak has underwritten accelerated aging tests and claims that its Infoguard disks should last 100 to 200 years. Maybe, maybe not. Despite such claims, some users have been chagrined and/or appalled to discover that data saved to CD/DVD was not readable after a few months. Eek!

I believe the more pertinent question is not how long data will remain on a CD/DVD, but rather how long will the storage device be available in the face of rapidly changing technologies? In other words, the DVDs and flash drives of today are going to be as usable as my 8-track tape collection at some point in the future.

As I've shared with subscribers of my fabulous (can there ever be too much hyperbole?) weekly newsletter (, I no longer use CDs and DVDs for backing up important data. I’ve had a few experiences in which I discovered that data successfully burned to CD/DVD was unreadable when I attempted to view it at a later time.

Today, for backups, I use external mechanical and flash drives that slip or plug into a USB port. Sometime before USB ports disappear, I will copy data to whatever the next generation of storage media is. Either that or I’ll finally say, “Oh, the heck with it all,” and sweep out the garage instead.

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