Sql – Installed Service Pack 3 for SQL Server 2005 but it does not show up when selecting @@version

I'm getting:

Microsoft SQL Server 2012 (SP1) - 11.0.3128.0 (X64) 

So yes - X86 means 32-bit, and in my case, X64 stands for 64 bit

and exec master.dbo.xp_msver returns:

4   Platform    NULL    NT x64

Again - x64 = 64-bit, while yours says X86 = 32-bit

IF EXISTS (SELECT * FROM sys.triggers WHERE object_id = OBJECT_ID(N'[dbo].[TRIGGERNAME]'))
DROP TRIGGER [dbo].[TRIGGERNAME]
go
IF  EXISTS (SELECT * FROM dbo.sysobjects WHERE id = OBJECT_ID(N'[dbo].[TABLENAME]') AND OBJECTPROPERTY(id, N'IsUserTable') = 1)
BEGIN
CREATE   TRIGGER [dbo].[TRIGGERNAME] ON [dbo].[TABLENAME] FOR INSERT, UPDATE 

AS ...

END

Based on your updated question... try this:

IF NOT EXISTS (select * from sys.objects where type = 'TR' and name = 'Insert_WithdrawalCodes')
EXEC dbo.sp_executesql @statement = N'

CREATE TRIGGER [dbo].[Insert_WithdrawalCodes] 
   ON  [dbo].[PupilWithdrawalReason] 
   AFTER INSERT
AS 
BEGIN
    SET NOCOUNT ON;
        UPDATE [dbo].[PupilWithdrawalReason] SET DateCreated=dbo.SYSTEMTIME() 
        WHERE WithdrawalCodeID IN (SELECT WithdrawalCodeID FROM inserted)
END


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