Today I was setting up new development environment with SQL Server 2014 and SSRS. After setting it up, I tried to connect to Report Manager (via URL specified in Reporting Services Configuration Manager) but I was constantly getting 404 page not found error.
Turns out that by default all unencrypted connections are being redirected to HTTPS, and since development machine I was using did not have SSL set up, I was getting 404 errors. Unfortunately Report Manager does not provide an option to turn off secure connection – the only way to do this is to change a setting in RSReportServer.config file manually.
Setting that needs chaning in RSReportServer.config file is called SecureConnectionLevel, and value needs to be set to 0 (by default value is 2, which means that secure connection is required).
Once setting is changed, save config file and restart reporting server.