I'm about to upgrade no se to a new Exim release. Do I need to ensure the spool is empty, or take any other special action?

It depends on where you are coming from.

1. If you are changing to release 4.00 or later from a release prior to , you will need to make changes to the run time configuration file. the file doc/Exim4.upgrade for details. If you are coming from re release 3.00, you should also see doc/Exim3.upgrade.

2. If you are upgrading from an Exim 4 release to a later release, you ot need to take special action. New releases are made backwards atible with old spool files and hints databases, so that upgrading be done on a running system. All that should be necessary is to all a new binary and then HUP the daemon.

Warning: If you have changed the release of your DBM library, so that your new Exim is linked with a different release than the old one, you may encounter errors when Exim attempts to access the old hints databases. See `FAQ/General_Debugging/Q0055`_.