Are previous versions of Canary software compatible with current versions?

Canary software is specifically designed from a user perspective allowing for a simple upgrade process.  

Historian Upgrades

Canary Historical Data Base Files (HDB) are backwards compatible from current versioning to version 5.  If upgrading from version 9 of the Canary Historian or older, you will want to uninstall first and then reinstall the Canary Historian.  Remember, always install the Historian first, then additional Canary applications (Axiom, TrendLink, etc).

Version 10 of the Canary Historian includes Store and Forward technology.  This means the Sender Service (if not local to the Historian) is capable of collecting and buffering data even if the Historian is offline.  When the Historian availability returns, the Sender Service automatically moves the cached data to the Historian.  This feature will allow you to upgrade the Canary Historian without worrying about data loss.

Axiom Upgrades

Axiom thin-clients use ClickOnce technology.  Simply update the Axiom Core (typically installed local to the Historian) and the next time the Axiom client is launched, it will automatically be updated.