I also asked a question over at StackOverflow which I ended up answering myself. Yesterday follow up information was added, which may be of use if you have trouble with the fix.

EY Kalman says:

I have had the same problem (on several different servers). Applying SP3 and Report Viewer SP1 has helped on some of the servers, allowing the client machines to connect and download the control with no problem. However, I have had one server that, even after applying the updates, when accessing the report viewer using a client machine, it was still giving me the error. On looking into the exact URL GET request that is being sent, I discovered that it is possible to force the client machine to connect directly to the Report Server to download the control.

The user would need to enter the following url:

http://reportservername/Reports/Reserved.ReportViewerWebControl.axd?ReportSession=51bjqv45xydgos2wghu5ceza&ControlID=7617dedbf0234f89b80cad8e64431014&
Culture=2057&UICulture=9&ReportStack=1&OpType=PrintHtml

This should then pop up the required download/install prompt.

dotnettrio added (which is probably more relevant to RSinteract):

Hi,

I got this working with out removing any patches. The above patch was not working too. Finally what I did was on the IIS server install the following patch and reset / restart the IIS server. This is not for report manager application. This is for any ASP.NET Web application developed in .net3.5 using VS2008 http://www.microsoft.com/downloads/details.aspx?familyid=6AE0AA19-3E6C-474C-9D57-05B2347456B1&displaylang=en

I hope this helps anyone else with this problem.

In the last week we’ve had three clients report a problem with our December release when running on Windows Server 2003 64 bit.

Server Error in ‘/RSinteract’ Application.

Could not load file or assembly ‘Microsoft.ReportingServices.Interfaces’ or one of its dependencies. An attempt was made to load a program with an incorrect format.
Description: An unhandled exception occurred during the execution of the current web request. Please review the stack trace for more information about the error and where it originated in the code.

Exception Details: System.BadImageFormatException: Could not load file or assembly ‘Microsoft.ReportingServices.Interfaces’ or one of its dependencies. An attempt was made to load a program with an incorrect format.

One of the issues we have experienced time and again with RSinteract is a scenario where the ReportServer/Database or Analysis services is on a different machine from RSinteract as demonstrated in the following diagram. The problem manifests itself as an authentication issue when Reporting Services tries to retreive information from the Database or Analysis server because Active Directory credentials expire after the first hop, in this case from RSinteract to Reporting Services.

Microsoft are calling this the “Double Hop” problem. The reason for Reporting Services’ and Analysis Services’ lack of integration out of the box is “in the interest of security”. Active Directory uses Kerberos under the hood which can be configured to pass credentials between web apps or not. To get this working with RSinteract or indeed any ASP.NET application you need to correctly configure Kerberos delegation.

I’m having trouble tracking down the steps for Reporting Services, the link I had has gone dead since I began writing this post

So here’s the steps to configure your Analysis Services (from Business Intelligence and Agile Development Blog):

1. Download and install the SetSPN utility (Either from the Windows Resource kit, or from http://www.microsoft.com/downloads/details.aspx?FamilyID=5fd831fd-ab77-46a3-9cfe-ff01d29e5c46&DisplayLang=en)
2. SETSPN is used to configure a “Service Principal Name”, which is required by Kerberos
3. Create a Service Principal Name (SPN) for the Analysis Services Instance (on the AS server)
4. (If AS is running as a domain account) setspn.exe –A MSOLAPSvc.3/
5. Configure Active Directory Settings
6. All users that are connecting to Analysis Services through the intermediate host need to be allowed to use Kerberos Delegation (”Account is sensitive and cannot be delegated” must be unchecked)
7. The “Account is trusted for delegation” setting must be checked for each user and each service account used in the process.
8. The “Trust computer for delegation” setting must be checked for each computer used in the process
9. Configure IIS Settings for the Virtual Directory hosting the application (or SharePoint site)
10. The Authentication must be set to “Integrated Windows Authentication” or “Basic Authentication”
11. The application protection level must be set to “High (Isolated)”
12. The impersonation level for COM+ must be set to “Delegate”
13. The COM+ application identity must be set to an account where “Account is trusted for delegation” is checked.
14. Connection strings must include SSPI=Kerberos
15. Connection strings CANNOT use IP Addresses

Here’s some more information pertaining to the bug:

• http://social.msdn.microsoft.com/forums/en-US/sqlreportingservices/thread/b8ba8546-76e8-46dc-a96e-bc61e847521f/
• http://www.sharepointblogs.com/kwanl/archive/2007/01/23/double-hop-asp-net-developers-beware.aspx

I’ll update this post as soon as I find the information for configuring SSRS.