Client yelled at me for 10 minutes about a 'virus' that was just his wireless mouse batteries dying
Had a guy bring in his desktop last Tuesday saying it had a virus because the cursor kept jumping around on its own. I ran every scan I had, pulled the drive, checked startup items, nothing. Then I noticed the cheap wireless mouse on his desk had a flickering sensor light, so I swapped in a $6 wired mouse from my parts bin and the problem vanished. He still didn't believe me until I showed him the old batteries reading 0.9 volts on my multimeter. How do you all explain 'this isn't a virus, it's hardware' without the customer thinking you're just trying to get out of real work?