It seems like shared dataset/datasource is not working if a report is used as a subreport. Please let me know if anyone is able to use shared dataset with subreport.

I have this problem for "preview" only. As soon as I deploy this to Reporting Service server it starts working fine.

Hi, Thanks for finding this question about shared datasource/dataset. Currently, there is no way to Preview the subreport with shared datasource/dataset in BIDS. I would suggest you submit a feedback at http://connect.microsoft.com/SQLServer/Feedback and hope microsoft correct it in the next release of SSRS service pack. thanks, Jerry

Did you submit feedback to MS? If so do you have the link so that I could recommend this gets resolved as well. Thanks!Matt Klepeis

I believe this is the feedback item your looking for: https://connect.microsoft.com/SQLServer/feedback/details/648560/subreport-with-shared-dataset-throws-error Although it also happens I believe when the subreport is using a shared dataset.