What does this sign mean?I see it in my score and don't know what I entered.I'd like to delete it. I am using the newer version of Reflow. MacBook Pro OSX El Capitan Ver 10.11.6
The symbol ¶ is known as a "pilcrow". In typography, it is a paragraph marker. The Wikipedia page on the pilcrow contains some information about its history and uses.
I don't know of any standard use in music for the pilcrow, and don't know why it is appearing in Reflow for you. I remember hearing about this symbol showing up in MS Word occasionally, when users inadvertently clicked the wrong menu selection; I think in that case there was a checkbox for paragraph marking. I don't know if Reflow has something similar.