There was an important and interesting post in the newsgroup recently that I have missed due to the MEDC and WinHEC conference attending.
The problem posted was about some API function (such as NPLogonNotify) not working under a full blown XPProEmulation XPe image. Obviously the issue was there not due to a missing component since XPProEmulation virtually includes all software components from the XPe database.
From the newsgroup thread you will see that the debugging the poster team has done showed that their own credential manager was working fine on Desktop OS and only failed to get notifications under XPe with interactive logon.
It appeared that the issue was there due to missing mpnotify.exe - the executable that is responsible for issuing Winlogon notification to registered network credential providers. The NPLogonNotify won't work if mpnotify.exe is not running (e.g., missing or crashed). Basically, it is the mpnotify.exe process who calls the NPLogonNotify function of the network provider .dll file.
The above fact is perfectly documented in this Microsoft Knowledge Base article.
The problems with XP Embedded is that although the mpnotify.exeis in the XPe Repository it doesn't belong to any component. It is basically left out from the component database which makes it harder to include in the image if you don't know what is required to get Network Providers to work and being notified by Winlogon.
A couple more useful links for the proper credential manager Dll integration into your image:
- Required authentication registry keys
- A very good guide written for Logon Filters - a sample credential manager from CodeProject.com.