Q I'm upset about what I consider a computer store rip-off. My daughter will be a college freshman in the fall, so we went to Best Buy and purchased an HP laptop and a $200, three-year warranty.

By that night, our daughter realized something was wrong with the PC and returned it to the store. A technician there removed the Norton security software that came with the PC because it was interfering with the Webroot security software we had purchased. Two days later, the PC was really slow, and she took it back to the store again. Best Buy said the PC was totally corrupted and replaced it for her. They also sold her their $40 computer optimization service.

I'm upset for two reasons. First, so many things should not go wrong with a new computer.

Second, Best Buy said we should've purchased the optimization service initially to remove all the (junk software) that comes with the computer. This might sound stupid or naive, but shouldn't a new computer already be "optimized" and at its peak?

And I don't understand why I should have to pay Best Buy for additional service after I'd already bought their three-year warranty. What else will I end up having to buy when something else goes wrong?

SUSAN THEISSEN, CHANHASSEN

A You've learned the hard way that buying a PC can be far from simple. Here's what I think happened:

You had the entirely avoidable problem of dueling Webroot and Norton firewalls. Two firewalls can't run simultaneously on the same PC; Best Buy should have warned you that the PC came with a firewall pre-installed.

The "corrupted" PC probably had a bad hard drive, an unavoidable manufacturing flaw that appears occasionally. (It's better for your daughter that the drive failed before she stored data on it.)

The computer optimization fee is partly the result of PC manufacturers and retailers working against each other.

Here's the problem: There isn't much profit margin in selling new PCs, either for the manufacturer or Best Buy. As a result, both sides try to sell PC-related services.

Computer makers make additional money by charging junk software makers to put their products on your new PC. This is typically advertising, which isn't harmful but slows down the PC.

Best Buy makes additional money by selling a "computer tune-up" service that partly involves removing the junk software the computer manufacturer put on. You could do this yourself, but if you're not sure how to do that, then you're wise to pay the fee. (The warranty covers only PC failure, not optimization.)

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