SSRS syntax error with countdistinct iif

Question

I have an SSRS report where I want to count specific results from the larger query (Overall Total - then of those total "Open" and total "Closed"). I'm trying to use the expression:

=CountDistinct(IIF(Fields!CaseStatusCode.Value='OPEN', Fields!CaseID.Value, Nothing))

But whenever I run the report I get:

There is a syntax error in the Value expression for the textrun 'Textbox24.Paragraphs[0].TextRuns[0]': ')' expected.

I've added and removed multiple ) but the error persists. I've also tried the expression in different textboxes and the error continues (just changing the name of the textbox it's in). What am I missing?

Answer 1

Solved it. Apparently I am supposed to use " instead of '. Corrected code below.

=CountDistinct(IIF(Fields!CaseStatusCode.Value="OPEN", Fields!CaseID.Value, Nothing))