Forefront/Microsoft Identity Manager – Attempted to access an unloaded AppDomain

This post is more a note-to-self for future me in case I’m in this scenario again. Today I encountered the errorĀ Attempted to access an unloaded AppDomain.

I have a custom Forefront/Microsoft Identity Manager Management Agent that requires multiple credentials for the Web Service it is integrating with. In order to secure parts of the credentials that cannot be provided as part of the Connectivity configuration tab on the Management Agent Proporties I have generated them and exported them using Export-Clixml as detailed in this post here.

Today I was migrating a Management Agent from one environment to another and was sure I’d regenerated the credentials correctly. However the Management Agent wasn’t working as expected. Looking into theĀ Applications and Services Logs => Forefront Identity Manager Management Agent Log ….

Forfront Identity Manager Management Agent.PNG

i found the following error ….

Unhandled exception, the CLR will not terminate: System.AppDomainUnloadedException: Attempted to access an unloaded AppDomain

Attempted to access an unloaded AppDomain.PNG

Retracing my steps, I had logged on to the Synchronisation Server with the incorrect credentials to generate my protected credentials XML file.

When the Synchronisation Server was running the Management Agent and attempting to run Import-clixml “credentialFilename” the credentials/account that had exported the credentials did not match the service account that the synchronisation server was running with. And the error listed above was thrown.


Import-clixml and Export-clixml do exactly what they are supposed too and respect the context by which the credentials were exported and will only be able to access them when imported under that same context. The error doesn’t really tell you that but does hint at it with Attempted to access an unloaded AppDomain if you know what you are trying to do.