Nothing

"Hey, any antivirus program installed on your PC?"
"Yes."
"Cool. Which please?"
"Nothing."
"Pardon?"
"Nothing."
"Sorry. Don't get."
"Antivirus, right?"
"Yes, please."
"On my PC?"
"Yep."
"Yeah, I have nothing installed."
"Oh, I see."
"Yeah."
"My bad then."
"How so?"
"I mean I thought I heard you say you have one installed but I guess I misheard..."
"Not at all. You did hear me right."
"Now, I'm confused."
"Really?"
"Yeah."
"Why so?"
"Do you have an antivirus program installed on your PC?"
"I do."
"Hmm...can you spell the name then, please?"
"N-O-R-T-O-N."
"What? Oh, please!"