Assembly Cannot Be Loaded From Network Or Azure File Share

Observed Behavior

Trying to run a package from a network path or an Azure File Share fails with the "System.Xaml.XamlObjectWriterException: Cannot create unknown type [....]" error.

For this scenario, the robot logs the following error message:

System.NotSupportedException: An attempt was made to load an assembly from a network location which would have caused the assembly to be sandboxed in previous versions of the .NET Framework.

Cause

The Azure File Share network URL where the package is found is not trusted by the robot machine or the account under which the robot runs does not have permissions to that location.

Resolution

Make sure that the account under which the robot runs has the necessary permissions. Then, add the Azure File Share network URL as a trusted site on the robot machine.