If the shared computer or server is not displayed on the desktop or in the "Finder" sidebar, or if you cannot connect to the server using "Go"> "Connect to Server", please try to follow the suggestions below.
Check the Finder preferences.
In the Finder on your Mac, choose Finder> Preferences. Click "General", and then make sure the "Connected Servers" checkbox is selected. Click the "Sidebar" and make sure the "Connected Servers" checkbox is selected.
Make sure the name you are querying is correct.
You may need to query the computer's DNS name or IP address instead of the computer's name.
Please consult your network administrator how to connect to the computer you are querying.
Make sure the computer or server is available. The
computer or server may have been shut down or restarted, or it may have been disconnected from the network. Please try to connect again, or contact the administrator of the computer or server. If the computer uses Bonjour or a Windows (SMB/CIFS) server, please make sure it is on the same local network or sub-network as your Mac. If the Internet connection firewall of the Windows (SMB/CIFS) server is turned on, you may not be able to connect to the server. [Note] If the computer is not on your local network or subnet, you may be able to connect to it by choosing "Go"> "Connect to Server", and then type its address in the "Connect to Server" dialog box.
Check your network connection
Your Mac may have been disconnected from the network.
To check the connection, open the Network panel of System Preferences (choose Apple menu> System Preferences, then click Network). The indicator next to your network connection type should be green. [Note] To connect, the server or shared computer and your Mac must be on the same network, or if you use "Go"> "Connect Service
For help connecting to a shared computer or server, please contact the owner of the computer or the network administrator.