Try

;with cte as (select *, count(Symbol) over (partition by [Name]) as Cnt from Symbology)

select * from cte where Cnt > 1

>symbology table as
>
>symbol char(6)
>name varchar(100)
>
>I want to select all the symbols that belong to names that have at least one match ( on the entire name )
>
>so if I have
>

>ATT          American Telephone and Telegraph
>ATT&        American Telephone and Telegraph
>ATTB        American Telephone and Telegraph
>AG            American Greetings
>AA            American Airlines
>AIR           Associated Industry Resources
>AUR          Associated Urban Renwal
>

>I only want to see
>
>ATT
>ATT&
>ATTB
>
>in the result set. Right now I am getting AG, AA AIR and AUR as they have matchs on the first three character.
>
>I want to group by name so that the only group having count(symbol) > 1 in the set above is the first three
>
>
>>Can you please translate in English what do you want to achieve? Better provide input and desired output.
>>
>>>I want to find all rows representing records that have at least one exact match on a varchar(100) column
>>>
>>>I am current doing
>>>
>>>

>>>SELECT 
>>>        name
>>>       ,symbol
>>>      ,from_date
>>>      ,thru_date
>>>  FROM [iSource100].[dbo].[Symbology]
>>>  where exists ( select Name, COUNT(symbol) as cntsym from Symbology
>>>  where thru_date > GETDATE()
>>>  group by Name having COUNT(symbol) > 1 ) 
>>>  and thru_date > GETDATE()
>>>order by name
>>>

>>>
>>>but from the results I'm getting it appears a 'match' for grouping seems to be based on just the first three characters of the Name column.
>>>
>>>How can I tell it to group by the entire contents of Name being an exact match?
>>>
>>>TIA