Troubleshooting HTTP Errors

This section provides cause and resolution information for the HTTP errors most likely to occur in a Reporting Services installation.

HTTP 400 Bad Request

If Internet Explorer returns "The webpage cannot be found" or an HTTP 400 error, the report server database might not be configured or be unavailable. Use the Reporting Services Configuration tool to verify the database is configured. Use the Services console application in Administrator Tools to verify the SQL Server Database Engine instance is started.

HTTP 401 Access Denied and HTTP 500 Internal Server Errors for Mismatching Authentication Settings

HTTP 401 and HTTP 500 errors can occur if there are conflicting authentication settings in the report server Web.config file and the RSReportServer.config file. To be compatible, the settings should be aligned as follows:


Web.config for Report Server





When these settings do not match (for example, if RSWindows* and Forms are specified for the same report server), an HTTP error will occur. The error that is returned will vary depending on whether a request was authenticated before the mismatch was detected. HTTP 401 is returned if the request fails authentication first; HTTP 500 is returned if authentication initially succeeds and then the mismatch is detected.

If you get either HTTP error after modifying authentication settings, verify that you updated both files correctly and that the settings align to the same authentication provider. For more information, see Configuring Authentication in Reporting Services.

HTTP 503 Service is Unavailable

HTTP 503 errors can occur during report processing or when you first access a report server:

  • If the report server is under high memory pressure, the report server will refuse new requests until the current application domain is unloaded and a new one instantiated. While requests are refused, you will receive HTTP 503 errors. If this situation persists, you should do one of the following: add more memory, move the report server installation to a computer that has more memory, or change the memory configuration settings. For more information about changing the configuration settings, see Configuring Available Memory for Report Server Applications.

  • For HTTP 503 errors that occur when you first open Report Manager or access a report server, you must review the HTTP.SYS log file for information about what is causing the error. By default, HTTP.SYS logging is not enabled. Use the following instructions to enable logging on your computer.

How to enable HTTP.SYS logging

  1. Copy the following lines into a text file

    Windows Registry Editor Version 5.00
  2. Save the file to the desktop as a .reg file.

  3. Double-click the file to apply the registry settings.

  4. Restart the HTTP service:

    1. Open a Command Prompt window. If you are using Windows Vista, open the window using Run as administrator permissions.

    2. Type net stop http.

    3. Stopping the HTTP service will cause other dependent services to also stop. To continue, confirm the action.

    4. Type net start http.

  5. Ping the Report Server Web service to send the request to HTTP.SYS and generate the HTTP 503 error. To ping the Web service, open a browser windows and type http://<your server name>/reportserver in the URL address.

  6. Open the log file in a text editor to view the entries. By default, the log file is located at %windir%\system32\LogFiles.