Error
"This Identity Cannot Be Opened With This Version of Entourage"
This message usually means, for example, that Entourage is at 12.0.0, but the saved database was saved in a more updated version. Since there was a database format change in there, Entourage 12.0.0 cannot open a database saved in later version.
Microsoft does not update each application every time an update is released. See “Confused over Microsoft Update Version numbers?“ for a handy script that gives you the Office application’s version info.
Users that have re-installed Office and find Entourage will not open:
There was an upgrade to the Entourage 2004 Identity shortly after release. If you update to at least 11.3.5, the Identity will open. You can find updater links here
The Entourage 2008 database also received an upgrade with SP1 (12.0.1) This means if you re-install from the DVD, your Identity will not open until you update to at least 12.0.1. You can find updater links here