DNA no common ancestor

I have read Peters DNA masterclass and followed all strategies, and this where the question comes from.
Shared matches- name that appears does not have a tree. Click on the name, there are no common ancestors and the match hasn't built a searchable tree. How do I find out where the connection is as its not a name I recognise from my ancestors. Upon contact with match they have no idea either?

 

Have you checked the Shared Matches? Sometimes you can narrow down the area where the person may appear by which matches they share, and if you can identify any of the matches that are there.

 

You may well not be able to find out how you connect to such matches and, as Peter suggests, it may be a wasted effort trying. A lot will depend on how close the match is.

You may be able to tell by looking at shared matches whereabouts in your tree the match may connect, and even if they don't have a tree, there may be clues in the person's Ancestry profile as to their approximate age, country of residence etc, but all too often there aren't.

I have lots of '4th cousin and closer' matches that I cannot identify, many of which I can't even tell which part of my tree they might connect to.

 

Thank you for all the comments. The reason I was interested was because they are supposed to be a 3rd cousin (a 3rd cousin that I do know we share the same great great grandparents) and the highest DNA match that my results have given, 118 cM across 7 segments, where the others are below 67cM across 3 segments, so naturally curious. I have followed the DNA masterclass by each strategy and didn't get any further info than already had, I am very lucky to have been handed down certificates that are over a hundred years old.
The surnames that I have not been able to find much about, I did the surname search on the DNA search and there are no matches.
So I decided to try and make the most of the results and go for the highest match.

 

Sometimes (like twice for me) simply Googling the mystery person's name has provided the clue via Facebook and/or Linkedin profile. Obviously may not be very useful when a name is common, but when combined with a familiar surname on the friends list it can provided the clue as who family could be and where to focus the genealogy research.
Then again I have a 230cM DNA match that remains unresolved even though from the shared matches I know exactly which branch of the family they are on.