It’s the mid-1990s, and this pilot fish is in charge of repairs for a computer store. “Most of my duties involved run-of-the-mill things like hard drive failures or memory upgrades,” he says.
But a new system comes back into the shop after just two days because the mouse won’t work.
Fish puts the PC on the bench and starts with the easiest possibility: He replaces the mouse. It doesn’t work, and the original mouse works fine on a known-good system.
He puts in a new card with a serial port and tries the mouse. No luck. He checks the Windows settings. They look fine. He starts replacing components, one by one: memory chips, video card, modem, sound card, floppy drive, hard drive, CPU and finally the motherboard.
Still no joy.
After two hours of misery, fish and the other techs are all staring at the machine, scratching their heads. That’s when the store’s owner, a friendly, soft-spoken guy, passes through the repair area and asks what’s going on.
Fish tells him the story. Owner asks, “What haven’t you replaced yet?”
Fish looks at the pile of components on his bench and shrugs, “Sheesh, I dunno — the case.”
Owner: “Replace the case.”
Fish: “I don’t know how that will make any difference. I’ve already rebuilt this thing about five times now.”
Owner: “Just try it.”
So fish pulls everything out of the old case, sets it aside, puts a new case up on the bench and rebuilds the machine from the original parts. He attaches the original mouse, powers it up … and the mouse works fine.
“Come to find out these cases were delivered to our shop completely empty except for one key component: the power supply,” fish says. “The power was spiking just enough that it was killing the serial connection to the mouse somehow.
Ever since then, says fish, “whenever we have a code problem and someone says that a certain troubleshooting idea can’t possibly be right, I tell this story. In all my years of doing this, I’ve found that it could always be anything!”
