When a parameter is set to a default value of (Null) and the report is saved to the sever, the default is lost when the report is re-opened in RB2. This problem doesn't seem to occur in BIDS. I've tried to use an expression to set the value to System.DBNull but this can no longer be done.Any ideas for a work-around?Is there a bug report open for this? I couldn't find an open bug on the Connections site and there's an issue on that site right now when submitting feedback.Paul Turley [Hitachi Consulting] SQLServerBIBlog.com

Hey Paul, not sure if you got around this but it's been a while but I just stumble in the same issue, what I did was, I chose the option "Administrate" of my report menu and I selected the option "Parameters" from the menu, there I could see that all the default value = null that I set up using the "Report Builder" were not set so I checked the boxes and press the "Update" button and it worked! better later than never...

Thanks for the post, Luke. I don't recall how I worked around it but did get the deployed report working (somehow). Pretty sure this issues was fixed in Report Builder 3.0 and the new version in SQL Server 2012 as well. Thanks for sharing your experience.Paul Turley, MVP, www.SQLServerBIBlog.com *Please vote if helpful*