Troubleshooting

Some adviсes about plugin troubleshooting.

1) NPS doesn't start/shows error after plugin installation.

First of all please check your operating system. It should be 64-bit either Windows Server 2008 or 2012R2.

I suggest you to manually install following packages before installing the plugin:
1) Microsoft .NET framework 4.5.2
2) Microsoft C++ Redistributables 2015

After installation of the plugin you need to check files in the installation directory.
Usually it's C:\Program Files\NPS.MAB.Extension.
Make sure the folder contains files mab.txt and log.txt.
As a test please set maximum permissions for all users (read/write/execute) for log.txt and give read permissions to mab.txt to the user who runs NPS service (usually it's LOCAL SERVICES but it's better to give read permissions to all users as a test).

In the "scripts" folder you can find a number of useful scripts for troubleshooting.
1) run "test_plugin_init.bat" to test if the plugin DLLs can be loaded sucessfully (you will likely see error message if it can't be loaded);
2) script "set_log_permissions.bat" helps to set necessary permissions like it's described above (sometimes it may not work because of system security restrictions).
3) script "unregister_plugin.bat" can be used to unregister the plugin and restore previous operation of NPS.
These scripts should be executed on behalf of administrator.

If the error remains please check system event viewer for NPS logs, application logs and system logs. The plugin itself writes events to the application log.

2) General troubleshooting.

Check application logs in the Event viewer (look for NPS.MAB.extension) to see how the plugin/authentication works.
You can enable additional debugging in the MAB Editor (Settings->Enable Debug) or by executing script "register_plugin.bat". The plugin writes debug information to the file log.txt located in the installation folder (usually it's C:\Program Files\NPS.MAB.Extension).

Below is a brief explanation how the plugin works:
The plugin loads mac-address database from mab.txt once it's loaded by NPS. The file is located in the installation directory (usually it's C:\Program Files\NPS.MAB.Extension). After that the plugin stores the database in memory.
The plugin checks time of last database update after every new authentication request. If it's more than 30 minutes passed since last update, the plugin reloads mab.txt file content.
If mac-address from authentication request doesn't exists in the database or there is an error during authentication request processing the plugin returns "Continue" result to NPS. It means the request will be checked by NPS against it's own authorization policies. If it didn't match any of the NPS policies then NPS responds with Access Reject code.
If client's mac-address is found in the plugin's database then it sends Access Accept message to the NPS and include additional attributes with vlan id (if configured).