Problem with executing sql-query

When I execute this query, I get the error: 'The colum prefix 'ClassifiedAd does not match with a table'. But the table does exist. Does anyone know what's wrong?

select ca.ItemID,
ca.ModuleID,
'CreatedByUser' = u1.FirstName + ' ' + u1.LastName,
ClassifiedAd.CreatedDate,
'UpdatedByUser' = u2.FirstName + ' ' + u2.LastName,
ca.UpdatedDate,
ca.AdTitle,
ca.AdText,
ca.AdHasImage,
ca.AdPOCName,
ca.AdPOCEmail,
ca.AdPOCPhone
from ClassifiedAd ca
left outer join Users u1 on ca.CreatedByUser = u1.UserID
left outer join Users u2 on ca.UpdatedByUser = u2.UserID
where ca.ItemID = 1
and ca.ModuleId = 1No it doesn't you've renamed it as "ca"