Is it ok to add comments/answers to old questions?
3302
Does it make sense to answer old questions?
108137
Is it OK to leave "What have you tried?" comments?
102781
When should I add another answer?
60643
Should Stack Overflow/Exchange have a mechanism for marking obsolete questions?
87154
What to do if an out of date question+answers already exists?
29720
Is it bad form to include information from other answers in your own answer (with references)?
61416
Should I vote to close old questions?
71646
Duplicates of an outdated question
75001
Does it make sense to put new or bad questioners in a "sandbox"?
12347
How should I handle questions which are answered in the comments?
112256
Should I still post an answer if I see several answers have already been posted while writing an answer or making a fiddle?
14629
Should I vote to close a duplicate question, even though it's much newer, and has more up to date answers?
97539
Etiquette for revision comments
61518
Old answers converted to comments shouldn't show up as new messages in the global inbox
86188
Get attention to a new answer to an old question
28528
Where should I post my sum-up of the answers, as the OP?
86307
Are comments on answers to my question supposed to show up in my recent activity