Can't locate the reply window

If you are trying to open a message and cannot see the reply window then try resetting the screen positions within SideNotesIM. You can reset the screen position by locating the yellow S icon in the System Tray of the lower right-hand corner of your monitor, clicking (or right-clicking) on it, and choosing "Reset Screen Position."

You can also reset the screen position from Options>System Options>Advanced and  choosing  "Reset Screen."