Stop in for a cup of coffee

Back in Norway a guy called me on the phone and told me I needed to clean up my windows. He sounded from India, based on his accent. I said: I didn't know my windows were dirty. Are you outside my house now, I asked the man? No, he answered. I asked him, if you are not outside my house, how can you know my windows need to be cleaned ? Is it the kitchen windows, or some of the others?
No, it is the windows on your computer he said. What computer I asked, what is that ? And the conversation went on and on for a long time about what a computer was, and the kitchen windows. I think we were talking for 10 minutes, finally he got upset and hung up on me.

Bill