I've got a problem. If an nhibernate-error occurs, I perform a rollback. But after this it's not possible to use the current session but I also don't want to restart the program. How can I create a new session?

>
> I've got a problem. If an nhibernate-error occurs, I perform a rollback.
> But after this it's not possible to use the current session but I also don't
> want to restart the program.


You have to Close session after Rollback. Even more - you have to close session after hibernate exceptions. Closing supposed to cleanup all the mess that caused exception and it will make all your objects Detached. To reattach these objects to newly opened session you can:
- call Session.update(detached_object) if your detached object is modified
- or call Session.lock if your detached object is not modified.

> How can I create a new session?

Well, do it the same way as you opened first session:)

I already tried it in this way, but it seemed that this does not work. I found an other error which was the problem...

to check if object is attached to session - call Session.Contains(obj)


To avoid "Contains, Update/Lock" sequence and minimize working
with Detached objects - you can consider "designing away" from
nhibernate-errors. I.e. try to make sure that they won't happen in
a first place. And when they happen that will mean that something
unpredictable (and possible unrecoverable:)) happened.