This is an old thread, but I figured I'd post something I learned here just in case anyone is having a similar problem. My report uses a parameter that, for prompting purposes, I defined as a drop-down list. It essentially is a string value that gets assigned by the drop-down to the parameter. It works fine when prompted in JasperServer. If I tried to pass that parameter in a URL, it always used the default value. The problem was that the Parameter Name in the report has to be exactly that same as the Parameter Name in the control. Jasper tells you that in the gray helper text on the Edit Input Control pane, but it's worth double-checking it. Sometimes it's the simplest solution that works!