How can I view my error log on UmbOne using .NET Core or .NET 5+ ?

To output your .NET Core or .NET 5+ errors to a disk file you will need to set the stdoutLogEnabled and stdoutLogFile attributes within the web.config

In your web.config you will need to update the aspNetCore attribute to look similar to below by adding the attributes in bold:

You can read more about this in the Microsoft Documentation here