1) Ensure that port 3050 is added in Control Panel -> Windows Firewall for both server and client
2) To add the port, go to Control Panel -> Windows Firewall, under Exception tab, click 'Add
Port'. Name : Firebird Port Number : 3050
Click 'Add' button.
if this cannot, try using Server IP instead of using computer name...
also checked that if there is any antivirus blocking the port.
check if firebird is running or not