A good question is duplicate of a bad question
13335
Someone flagged my question as already answered, but it's not
22458
Add ability to flag answers as duplicates
31058
Responding to a poor question
100366
What is best way to find duplicate questions?
25926
Why can't I accept two answers for the same question?
146225
Duplicate questions on other SE sites?
71646
Duplicates of an outdated question
18551
Duplicate questions in feed, and questions incorrectly marked as unanswered
18509
Does the new guidance on duplicate questions suggest closing a question as duplicate, if the original answers the OP's question?
19629
Where is it preferred to place the answer to duplicate questions?
132695
Did SO used to have fundamentally different rules about what constituted a good question (see example)?
38321
Why was an answer allowed on a question that was merged into another one?
131258
Dealing with bundle/omnibus/list-of-questions question that consists of rather distinct questions
51087
Remove votes to close question X as a duplicate of Y if question Y is closed as a duplicate of X
112391
How should one respond to "duplicate answer" flags?
104491
Single question thread with multiple questions, some duplicates
118752
Is it wrong to ask the same question elsewhere?