Problems Accessing (Synology) NAS over AFP directly over the finder and time machine with Mavericks MBPr we have two Macs, an older iMac and a MBPr both with Mavericks (10.9.3). Only one of them has a very annoying problem with our new synology ds214+.

With the iMac I can access the NAS over the the finder symbol (both AFP and SMB). Also time machine finds the time machine folder on the NAS which was configured over the synology dsm software. 

The MBPr on the other hand can access the NAS over different ways: AFP from the browser "afp://ip.adress", smb over the finder symbol. 
But there is no way I can get it to work with time machine or AFP over the finder symbol. I just get a message saying something like "While connecting to 'DiskStation' an error occured. Maybe the server is not available anymore".

I have a hands off! firewall installed, but it doesn't matter if it is turned on or off.

Due to the fact that it worked for one night with the first backup i am kinda driving crazy, cos ever since I can't get it to work again. I even tried to reinstall OS X from a backup with no success either.

I am wondering if there might be any connection to the fact, that my MBPr doesn't connect to the apple software update server either.

I am thankful for any advice.
add the nas hostname and IP to the MAC "hosts" file, that's how fixed it today.

to edit the host file on a MAC, best way is through terminal, google it.

Good luck