Retrieving url parameters

I have a 2 reports - Product Master and Product Details. I have the ProductID parameter being passed properly from the Master via the URL to the Details Report, but the Details report doesn't seem to be picking up the paramater from the URL and keeps prompting for the ProductID.

What settings should I be configuring in my Details report to say - "Get the parameter from the URL"?

I've tried multiple configs within the Report Parameters dialog box but I seem to be missing something...

?

In the first report, on the navigation tab for the textbox:

Choose the Report action, choose a report or enter a path to the report and then click the parameters button. Provide the values you want. you can use an expression here which is something like Parameters!ParameterName.Value which will pass to the drill-through report the same value as was passed to the original report.

Hope that helps,

-Lukasz