First of all, check that your connection is not blocked by firewall.
Error numbers mean that you have no connection to the server.
After that please try to connect to your database using firebird
command line tool isql.exe. If you will be able to connect with isql,
the problem is in your program (or it's settings). If not - this is more
general connection problem (like firewall, for example).
By the way - where is your firebird server installed ? If you are
trying to connect to the server installed on the same machine, try to
connect via localhost instead of local protocol.

Best regards,
Pavel Kutakov
SQLLY Development.
InterBase/Firebird Development Studio - complete development solution.
http://www.sqlly.com