Event ID 686 — Federation Service Proxy Logging

Applies To: Windows Server 2008 R2

You can use Active Directory Federation Services (AD FS) log files to troubleshoot issues with the federation server proxy. The creation and updating of AD FS log files are monitored here.

Event Details

Product: Windows Operating System
ID: 686
Source: Microsoft-Windows-ADFS
Version: 6.1
Symbolic Name: DebugLogCannotStart
Message: The AD FS troubleshooting log was not able to start.

An exception has been thrown, and the application pool that hosts the BoundedSizeLogFileTraceListener will not be able to start.

Additional Data
Exception message: %1


Create a log directory and assign the appropriate permissions to the user

If access to the log directory is denied, assign the appropriate permissions to the user. If the log directory is not found, create one. The location of the log directory is specified in the web.config file.


Verify that Active Directory Federation Services (AD FS) log files have been generated in the log files directory.

To perform this procedure, you must be a member of the local Administrators group, or you must have been delegated the appropriate authority.

To locate the log files directory

  1. On the federation server, click Start, point to Administrative Tools, and then click Active Directory Federation Services.
  2. In the console tree, right-click Federation Service and then click Properties.
  3. On the Troubleshooting tab, check the location of the log files under Log files directory.

Federation Service Proxy Logging

Active Directory Federation Services