SCCM Configmgr Unable to run SSRS reports due to HTTP 500 Internal Server Error

Setting up Configuration Manager current branch (1702) lab for testing. While running the Configmgr reports using IE browser ,http://servername/Reports/Pages/Folder.aspx ,it failed with error code HTTP 500 Internal Server Error. SQL server installed locally on Configmgr box . I have seen this error couple of time but i don't remember what was the solution to get…