--First create a test table
IF OBJECT_ID('TempDB..#Test','u') IS NOT NULL
      DROP TABLE #Test
CREATE TABLE #Test
(
Col1 VARCHAR(20),
Col2 VARCHAR(20),
Col3 VARCHAR(20),
Col4 VARCHAR(20),
Col5 VARCHAR(20)
)
GO
--Then insert the test date, with lines 6 and 7 being dupes
INSERT INTO #Test
SELECT 'Blue','is','the','first','pair' UNION ALL
SELECT 'Orange','is','the','second','pair' UNION ALL
SELECT 'Green','is','the','third','pair' UNION ALL
SELECT 'Brown','is','the','fourth','pair' UNION ALL
SELECT 'Slate','is','the','fifth','pair' UNION ALL
SELECT 'Orange','is','the','second','pair' UNION ALL
SELECT 'Brown','is','the','fourth','pair'
GO
--Add an identity column to the table for use in deleting the dupes
ALTER TABLE #test
      ADD ID INT IDENTITY(1,1)

GO
--Check #test first
SELECT *
  FROM #test
--Delete the dupes
DELETE t1
  FROM #test t1,
      (--Select the MIN ID of the dupe records.  It only stands to reason
       --these were in the table first
       SELECT 
             MIN(t1.id)ID ,t1.col1,t1.col2,t1.col3,t1.col4,t1.col5
         FROM
             (--Derived table t1 selects all the dupes, based on the columns you specify
              --you would need to add any columns you want to look at as being criteria
              --for dupe records
              SELECT
                    t1.*
                FROM #test t1,
                     #test t2
               WHERE t1.col1 = t2.col1
                 AND t1.col2 = t2.col2
                 AND t1.col3 = t2.col3
                 AND t1.col4 = t2.col4
                 AND t1.col5 = t2.col5
                 AND t1.id <> t2.id
              ) t1,
                #test t2
        WHERE t1.col1 = t2.col1
          AND t1.id <> t2.id
     GROUP BY t1.col1,t1.col2,t1.col3,t1.col4,t1.col5
      ) t2
 WHERE t1.col1 = t2.col1
   AND t1.col2 = t2.col2
   AND t1.col3 = t2.col3
   AND t1.col4 = t2.col4
   AND t1.col5 = t2.col5
   AND t1.id <> t2.id
--Check #test after deletion
SELECT *
  FROM #test