Over the years, I've handed out a lot of advice in this column. Most of it, I hope, is good. But some of it isn't. So I'm 'fessing up to a couple of mistakes.
Take the matter of backing up your hard disk. With huge drives that hold hundreds of megabytes as standard equipment today, backups have become difficult and time consuming, if not downright impossible without a tape unit.
Still, until recently it was quite possible to protect your most important investment merely by backing up your critical data files -- your financial records, word processing documents, spreadsheets and so on. That's what I advised.
For example, if you were using WordPerfect, there was no need to back up the entire four or five megabytes of WordPerfect program files -- just your correspondence and reports. If your hard disk crashed, you could always reinstall the software itself from the original floppies in a few minutes.
Unfortunately, all that has changed with the advent of Microsoft Windows. Windows is a complex graphical operating environment that can run multiple programs simultaneously. Those programs must to be able to communicate with Windows and with each other.
The result is an installation nightmare. When you install TC Windows program, it may put critical program files in its own directory (where it should be), in your Windows directory, or in the Windows system subdirectory. It may set up its own initialization files, or modify the basic Windows initialization files.
There's no standard for this. Each software publisher plays by his own rules, and it's incredibly frustrating -- even for sophisticated users -- who have no idea what changes have been made to their system once they install a program.
So here's my tale of woe (I feel better already, just talking about it). Over the weekend, I installed a new CD-ROM drive. People do this kind of thing on the weekend because that's when they have a few free hours. But it's the worst possible time to make major changes because if something goes wrong, most companies' technical support lines are closed.
For a variety of reasons that I'm still puzzling over but won't bore you with, something went wrong, and suddenly I was getting errors from my main hard drive. Most of the problems involved programs in the Windows directory. Why Windows, I don't know.
Luckily, I had backed up most of my important business and word processing files, and I scrambled for a couple more hours to back up onto tape everything else the hard drive would read before I dealt with the problem.
After a few more hours re-seating controller boards and playing with a variety of disk repair utilities, I confined the damage to the Windows directory. I hadn't lost anything valuable -- or so I thought. I should have known better.
When I reinstalled Windows, nothing was left of the old program groups, icons and other goodies that I had developed over the last few years to make my computer work comfortably for me.
Worse yet, when I tried to start my word processor, data base and other software, I got all kinds of errors, because those programs were depending on critical files they had stashed in Windows directories that had been wiped out. In short, almost nothing worked.
So far, I've spent five or six hours reinstalling all my Windows software, and I figure I'm about halfway to getting things working the way they were.
My conclusion: If you're running a variety of Windows programs, back up everything that's even remotely connected to Windows.
Unfortunately, we're talking about an additional 20 to 50 megabytes of program files, which makes for a lot more work than copying a handful of data files to floppy disks. You can create this kind of backup on floppies, but if your time is valuable, invest in a tape backup unit and use it regularly. They're available for as little as $250, and they're well worth the expense.
Next confession. A few weeks ago I recommended that users power down and unplug their PCs when a thunderstorm draws near, implying that there's little danger when the storm starts to move away.
That brought a friendly and informative call from Vladi Bash, a power quality consultant for Baltimore Gas and Electric Co., who spends much of his time showing customers how to avoid power problems and figuring out what happened when they do get zapped.
Mr. Bash advised me that sensitive electronic equipment is in peril whenever lightning is in the area, because a strike on power lines or a substation causes the whole local grid to shut down -- sometimes for the blink of an eye, sometimes for a second or more -- until stable voltage can be restored. This is what's happening when your lights flicker on and off during a thunderstorm.
Those little flickers find an easy target in the logic circuits of hard disk drive heads, which can become confused and crash, he said.
Mr. Bash recommends protecting against these glitches with a good uninterruptible power supply (UPS), a stand-alone battery backup that kicks in immediately when the power goes off.
He cautioned against using the very cheapest models, because they often aren't quick enough to deal with the very interruptions that accompany strikes on the power grid. It's hard for a novice to tell whether a UPS can handle this kind of problem, and the difference in price may be only $25 to $50. But a good sign, he said, is a guarantee that the unit will protect your equipment, instead of a disclaimer that absolves the manufacturer of all liability should the equipment fail you. Also, look for an Underwriter's Laboratory 1778 sticker, which means the box has passed safety tests designed for UPS units.
(Michael J. Himowitz is a columnist for The Baltimore Sun.)