Access 2000 Report Writer prompting for value

[bojbrown]

I have added an unbound text box and have given it a name 'XAmt'. In one of the footer sections, I have another unbound box with a control source of
=SUM([XAmt]), which follows many of the examples I have seen. XAmt has a control source of =IIF([TXN_AMT] = 5,[TXN_AMT],0) and TXN_AMT is a field on the report from my data source.

But when the report starts to print, it prompts for a value for XAmt. Why? Isn't this how you would do special calculations on a report and sum them?

Thanks for anyone's help.

 

[Rich]

you can't Sum calculated fields in this way, repeat the calculation
Sum(IIF([TXN_AMT] = 5,[TXN_AMT],0))