> If FlameRobin can open it without exceptions, what makes you think it's corrupted?

Well I'm not sure it is corrupted, but something is wrong. The file that was opening fine in my application now causes the error as shown in the first post so something is "broken" in the file. I have to admit I know very little about firebird. Could the file be in some sort of locked or unresolved state? As I said I've never seen this happen before and is somewhat concerning. We use a database for data storage partly for the security against crashes so I have to get to the bottom of this.

>
> windowsXP + "E:\dbfile.gdb" - the well-known, documented-to-death case is an obvious cause. Try changing the file suffix to ".fdb".

What are you referring to here? Can you point me to a link? What difference does the extension make?

>And don't try to start your app if FlameRobin or another instance of >your app is already connected to the database: that will cause an >i/o error too.

Yep, I figured that one out.

Thanks for your help,
Felix