How to enable Schannel event logging in IIS

When you enable Schannel event logging on a computer that is running Microsoft Windows NT Server 4.0, Microsoft Windows 2000 Server, or Microsoft Windows XP Professional, detailed information from Schannel events can be written to the Event Viewer logs, in particular the System event log. This article describes how to enable and configure Schannel event logging.

Enable logging

Warning Serious problems might occur if you modify the registry incorrectly by using Registry Editor or by using another method. These problems might require that you reinstall your operating system. Microsoft cannot guarantee that these problems can be solved. Modify the registry at your own risk.

Note This registry key is present already in Windows 2000 and XP Professional.

1. Start Registry Editor. To do this, click Start, click Run, type regedt32, and then click OK.
2. Locate the following key in the registry:
   HKEY_LOCAL_MACHINE\System\CurrentControlSet\Control\SecurityProviders\SCHANNEL
3. On the Edit menu, click Add Value, and then add the following registry value:
   Value Name: EventLogging
   Data Type: REG_DWORD
   Note After you add this property, you must give it a value. See the table in the "Logging options" section to obtain the appropriate value for the kind of events that you want to log.
4. Exit Registry Editor.
5. Click Start, click Shut Down, click to select Restart, and then click OK to restart the computer. (Logging does not take effect until after you restart the computer).

Logging options

The default value for Schannel event logging is 0x0000 in Windows NT Server 4.0, which means that no Schannel events are logged. In Windows 2000 Server and Windows XP Professional, this value is set to 0x0001, which means that error messages are logged. Additionally, you can log multiple events by specifying the hexadecimal value that equates to the logging options that you want. For example, to log error messages (0x0001) and warnings (0x0002), set the value to 0x0003.