Problems with exec on a SQL String

Hi,
Currently creating a dynamic string in a Stored Proceedure. Having problems incorporating a variable declared as type datetime. Here is the string - anyone help?
Getting the error - Syntax error converting datetime from character string.
Already tried CONVERT function

INSERT INTO #res1 SELECT *FROM cust_submitter WHERE ORDERID IN (SELECT GMREF FROM GMDB..GMDB.ORDERS WHERE ACCOUNT_MANAGER = ' + @manager + ') AND DATE_COMPLETED >=' + @startdate + ' and DATE_COMPLETED <=' + @enddate + '' + CHAR(13) +

Cheers

You may need to try something like this:

Code:

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Declare @Sql As VarChar(1000)

Set @Sql = 'INSERT INTO #res1 '
Set @Sql = @Sql + 'SELECT * '
Set @Sql = @Sql + 'FROM cust_submitter '
Set @Sql = @Sql + 'WHERE ORDERID IN (SELECT GMREF '
Set @Sql = @Sql + '                  FROM GMDB..GMDB.ORDERS '
Set @Sql = @Sql + '                  WHERE ACCOUNT_MANAGER = ' + @manager + ') '
Set @Sql = @Sql + ' AND DATE_COMPLETED >= "' + Convert(varchar(10), @startdate, 101) + '" '
Set @Sql = @Sql + ' And DATE_COMPLETED <= "' + Convert(varchar(10), @enddate, 101) + '" ' + CHAR(13)

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