Assistance with file sharing.

Hi,

I wish to access another mac(iMac21) on from imac27 on my home network. I am able to connect to imac 21 as I can see it in Shared in finder. However when I click on the imac21 in Finder it does not open. I do not see the folders on the mac21. I have selected file sharing, printer sharing and screen sharing on both macs. So any ideas as to why I would not be able to see list of shared folders on the other mac despite seeing the computer name in the Shared portion of the Finder sidebar. Is there a setting I am missing?

Once resolved I would then like to be able to see an external drive from the mac21 in finder. So that I do not always have to connect to the computer namefirst and then access the external drive.

Thanks and I look forward to your reply.

...Bruce