[otrs] otrs version 2.0.2

I have installed otrs version 2.0.2 on a Linux operating system and everything seems to be ok but the link on the ticket screen for "Compose Answer(email)" is missing. I tried googling for information on this but from what I found in the previous versions of the otrs manuals, the link should just be there. There does not appear to be any setting that I need to set in order to activate it. Does anyone know how I can fix this so that the "Compose Answer(email)" link is available for use when the ticket is opened? Linda