I have created a few reports with DateTime parameters. Everything work ok with the designer. Now I have a report with a long parameter. All other parameter settings are the same as with the DateTime parameter reports. When I preview the report in the designer it says I need to supply a parameter just like to other reports. I enter the parameter but the preview button is disabled and wont print. I tried re-creating the report and the same thing happens. I go back to the other reports and the preview enter parameter works. Why is the preview button disabled? If I supply a default value for the parameter all works ok.