Create a new data source in SQL server reporting services window and load new report files

Click New Data Source.

Enter a Name e.g. DataSource

Enter the connection String e.g.:Data Source=SERVER NAME; Initial Catalog=DATABASE NAME

Within Credentials Stored securely in the report server enter the user name and password.

Select Test Connection

Click on OK.

Select Upload file

Click on Browse and find the .RDL file you want to load.

Select Manage in the report drop down

Select Browse to Select a shared data source

Select DataSource1 then click OK

Select Apply.

Now simply click on the report to Run it.