I have a desktop application with a single error handler at its event loop. All that handler does is show the exception message in a messagebox and then the event loop resumes. This application has a "save file" option.
In this application it doesn't matter if the permission is denied, the path exists and is a directory, it was a network share that went away, or a disk write error, or out of memory, or a bug. If I press "Save" and the exception occurs, I can read the message and correct the problem if possible, and then just press Save again. It is incredibly robust and has effectively no error handling.
Of course, that doesn't handle all the cases that you describe. For example, for your case #1 I think that isn't a case that no more meaningful work can be done and isn't an error. Instead, you're just asking a question and then proceeding or not based on the answer.
In this application it doesn't matter if the permission is denied, the path exists and is a directory, it was a network share that went away, or a disk write error, or out of memory, or a bug. If I press "Save" and the exception occurs, I can read the message and correct the problem if possible, and then just press Save again. It is incredibly robust and has effectively no error handling.
Of course, that doesn't handle all the cases that you describe. For example, for your case #1 I think that isn't a case that no more meaningful work can be done and isn't an error. Instead, you're just asking a question and then proceeding or not based on the answer.