Besides the fact that order by doesn't seem to make sense in your query.... To use order by in a sub select you will need to use TOP 2147483647.
SELECT (
SELECT TOP 2147483647
COUNT(1) FROM Seanslar WHERE MONTH(tarihi) = 4
GROUP BY refKlinik_id
ORDER BY refKlinik_id
) as dorduncuay
My understanding is that "TOP 100 PERCENT" doesn't gurantee ordering anymore starting with SQL 2005:
In SQL Server 2005, the ORDER BY clause in a view definition is used only to determine the rows that are returned by the TOP clause. The ORDER BY clause does not guarantee ordered results when the view is queried, unless ORDER BY is also specified in the query itself.
See SQL Server 2005 breaking changes
Hope this helps, Patrick