[technical problem]
"Please give more details, like OS, hardware, …"
"you see i'm working on pc."
Oh, alright, so I have to start at the very beginning... *starts explaining that more than one OS exists and that you can do different things with your computer*

I used to determine which version of windows they were using by asking the shape and location of the start button.

Much easier than walking them through opening system properties, the terminal, or pushing shortcut combinations. Ugh. I do not miss tech support.

@snaz Well, actually PC can be equal to Windows, since the name PC has been nominated by Microsoft, just like Mac.

@Root It's not even real tech support. I'm following some tags on gaming.stackexchange.com, but the subscription mails don't care about the fact that I "ignore" (make the site hide) questions with the "technical-issues" tag, also it's usually not added by the asker. That tag just has the worst questions on that website, full of people like that.