That is likely because you setup access to be via account, and have not put in the account info.
In finder, top menu, Go, Connect to server, type in the address..
AFP://TCname or TCIPaddress where you replace that generic name with the actual name or IP obviously.
When you do this you will get a request for password to the this account.. this will only work if the account name setup up on the TC is the current account you are logged into on the computer.
If you are trying to use a different name you need to login using that user name.
AFP://username@TCname
Where obviously you replace username with the account name on the TC you are trying to connect to.
Apple of course had to do some breaking in Mavericks.. they usually break something.. SMB is what they broke this time around.. But SMB is now used for Mac file sharing not AFP.. at least that is the article I read.
http://www.tuaw.com/2013/10/27/did-mavericks-kill-your-network-drive-access-here s-a-fix/
The suggestion is to use CIFS://networkshare_name. Which uses older and unbroken SMB1 instead of apple's broken SMB2.
Note this article.
http://support.apple.com/kb/HT5884
SMB is now default for Apple.. and not AFP. (The world becomes an ever stranger place!!)