I have not solved yet my problem of connection to a database.
The installed version of my program + database runs correctly on my
PC.
But I have an error on the other PC where I made a fresh
installation (Firebird server + installation of my program and its
database).
Firebird runs correctly and I could open the database with IBeasy.
But when running my application, the path is not recognized or there
is another problem. I thought that may be the password could be in
cause, but even if I change the password of sysdba to have it in
uppercase, it does not make any difference.
A friend told me that perhaps I should add the server name in the
path : this does not work either. And also that I should write the
path in the registry. I will do it later but I am convinced that it
could work correctly with the code as it is since it works on my
machine.
Should I redownload a version of Ibobjects ?
I did not intend to buy the components before having tested a
distribution of my program, is the version of ibo being evaluated
the problem ?
Here is the code which is included in my previous message :

FDBPath := ExtractFilePath(Application.ExeName)
+ 'Database\BDCOCAGNE_PLC.FDB';
With DM_Cocagne do
begin
with IB_Connection1 do
begin
Connected := False;
LoginPrompt := False;
Username := 'SYSDBA';
Password := 'masterkey';
Server := '';
Path := FDBPath;
Protocol := cpLocal;
Connected := true;
end;
with IB_Transaction1 do
begin
if InTransaction then Rollback;
AutoCommit := True;
IB_Connection := IB_Connection1;
Isolation := tiCommitted;
RecVersion := True;
end;
end;

I decided to activate the login prompt instead. But I still have the
same problem.
It seems as if the path is set to blank.