In all of these sentences I chose past simple. Do you think present perfect is possible too?
1.When did you meet him?
When have you met him?
2.Where did you put the newspaper?/Where have you put the newspaper? I want to read it, but I can't find it anywhere.
3.Why did you put all the things in the wrong place?
Why have you put all the things in the wrong place?
4.Why did you leave the door open? You will catch cold sitting in the draught.
Why have you left the door open? You will catch cold sitting in the draught.
5.What books did you read/have you read when you lived in the country? (I think only 'past simple' should be used here.
Could you tell me in which of these examples it is also possible to use present perfect? Is it wrong to use present perfect after 'when'?
I strongly believe we can't say "When have you met him?"
We teach not to use present perfect with 'when' as a question word.
In the right context, we can.
A. I've met Tom Cruise.
A. Yes, really. He was very nice.
B. I don't believe you.
A. Well, it's true. I have met him!
B. Oh, come on! When have you met Tom Cruise?! (The word "you" would probably be very heavily stressed and the tone of voice would be incredulous.)
A. Last year, in the lobby of a hotel in L.A.
I agree that "When did you meet him?" would sound better as a standard question but there is something in the intonation of disbelief or surprise that leans me towards "... have you ...?"
Remember - correct capitalisation, punctuation and spacing make posts much easier to read.
I agree with bhai and ems that the present perfect is possible in that sentence in the right context.