Give the ability to have the reports viewer show the criteria used in running the report. Many times there are hard-coded criteria that the user cannot see. For example, we have a report that has no user-selectable criteria - just a Refresh button to execute the report. It shows results based on certain date fields being blank but the user has no way of knowing (unless written into the report itself) what those criteria are. Other reports allow the user to select a date range and they are displayed as Begin Date and End Date, but the results show three date columns. If there was an information bar as part of the reports viewer that showed the criteria passed when generating the report (or a button that the user could click to see the criteria used) this would help end users immensely. For example, the bar could show something like "Criteria: Closing Date >= 01/01/2014; Closing Date <=12/31/2014; Status <> Cancelled"

I had to add these buttons myself! and apparently when I want to print what's in the viewer, I have to render the content to html before !

Why is it that when it comes to a winForm application, users will be needing to print and export their reports, but when it comes to web applications it's not that much of a need?
We don't just need to display reports just to display them, okay sometimes maybe we do, but in most cases it's either about the printing or about the exporting.
I know I can use the FlashViewer instead of the HtmlViewer, but then every user will have to update his flash player (and if he has not the right version, he wouldn't even know that he has to update it, because no error shows up! just no viewer).