>D:\my_app\fbclient.dll

What's this file? It should be fbembed.dll renamed to fbclient.dll. If it's not, then it's the regular client API and you're getting the error because there's no server.

Yes this is fbembed.dll from the Firebird-2.5.2.26539-0_x64_embed.zip root folder renamed to fbclient.dll. 

Also I'd want to check that your application (either via path name or using an alias) is connecting to a database path and not an unqualified file name for the DB. The server is embedded but it's still a server, not a file jockey.

The database path I am using in both my app and IB_SQL.exe is simply the atabase name "myapp.FDB". 

When fb_inet_server.exe is running as a background process on the machine both my app and IB_SQL.exe connect to the server and the app runs as I would expect.

Adam
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