>>Until recently I was using version 2.0 and now I use 2.5. I encountered a problem that bothers me, is about the message when they enrolled in >>the database when the condition is not met foreign key. In version 2.0 messages contained the names of tables and foreign key, now in >>version 2.5 I get messages like (@ 1 @ 2).

Sounds like you are still using the FB 2.0 FBClient.dll for connecting to the FB 2.5 server. Check what versions of FBClient.dll and GDS32.dll you have floating around, which might be getting used.