Updating from Visual Studio an existing SSRS CRM report (e.g. Activities) may require an external reference to the assembly Microsoft.Crm.Reporting.RdlHelper.dll. This assembly contains several helper functions which can be used from your report.
This assembly can be found in the SSRS report server, normally in the next folder:
C:\Program Files\Microsoft SQL Server\MSRS10.CRMRS\Reporting Services\ReportServer\bin
An easy way to make this reference works is your Visual Studio is to deploy the same assembly into the GAC of your desktop
In my case, I updated the Activities (parent) and Activities Detail (child) reports to include Accounts as part of the regarding. Out of the box, this report only provides the activities linked to Incidents and Opportunities.
Basically, I followed the next steps:
1) Download SSRS report from CRM. Edit Activities report => Actions => Download report and rename it. Repeat the same for Activities Detail report
2) Open Activities report from Visual Studio
3) Deploy RdlHelper.dll in the GAC of my desktop
4) Edit DSActivity dataset query to include accounts (both reports, parent and child)
5) Include new parameter CRM_FilteredAccount (both reports, parent and child)
6) In your new renamed Activities report, update series action to go to new child report. From Design View, right click on the series => Series Properties =>Action => Go to report and selecte the new child report, the one renamed from Activities Detail. Just in the same form, add a the new parameter CRM_FilteredAccount – [@CRM_FilteredAccount]
7) Upload your new reports to CRM.
8) Set up the parent report for the new child report Activities Detail.
I hope it helps.