I need to be able to scroll a RichTextBox to the bottom, even when I am not appending text. I know I can append text, and then use that to set the selection start. However I want to ensure it is at the bottom for visual reasons, so I am not adding any text.
You could try setting the SelectionStart property to the length of the text and then call the ScrollToCaret method.
richTextBox.SelectionStart = richTextBox.Text.Length;
richTextBox.ScrollToCaret();