I got the answer from link "https://www.sqlskills.com/blogs/tim/issue-publishing-to-ssrs-2012-with-ssdt-2015/"
Issue publishing to SSRS 2012 with SSDT 2015
By: Tim Radney
Posted on: January 22, 2016 2:58 pm
I recently was helping a client who was trying to use SQL Server Data Tools 2015 to update and generate reports that would be deployed to SQL Server Reporting Services 2012. When trying to deploy the report, the client would get the following error:
“[rsInvalidReportDefinition] The definition of this report is not valid or supported by this version of Reporting Services. The report definition may have been created with a later version of Reporting Services, or contain content that is not well-formed or not valid based on Reporting Services schemas.”
I knew that SSDT 2015 should be backwards compatible and able to work with multiple versions of SQL Server products, so I had to do a little research to figure out what exactly needed to be changed in order to publish a report to SSRS 2012.
In my lab, I created a new project named GetDatabases. This project was a basic report that would get query a system table. The first thing I tried to change in the project was the TargetServerVersion located under the project properties.
I updated the TargetServerVersion to “SQL Server 2008 R2, 2012, or 2014”, the default in was “SQL Server 2016”. I also updated the TargetServerURL to my development server running SSRS 2012. I made these changes to both the release and debug configuration options.
After making these changes, I was still unable to deploy the report. After a bit more research, I found a location to change the default deployment server version of the Business Intelligence Designer. This is located under ‘Tools and then Options’. The default was set to version 13.0, once I changed the version to 11.0 to match the server I was deploying to, I was able to successfully deploy my report to SSRS 2012.
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