Microsoft's Windows Update automatically downloads and installs modifications to your Windows system.
On 12 October 2005 a batch of updates was released through Windows Update. One of them (identified by Microsoft as "KB896688") stopped macros from working in Cardbox. Cardbox was not the only program affected: a search for "KB896688" or "896688" in Google Groups shows many reports of problems.
If you are using the Home Edition of Cardbox then this almost certainly does not affect you, since the recording and creation of macros aren't part of the Home Edition.
If you are using the Professional Edition and are using macros, then you will find that many macros halt with the message "Macro tried to create an object of an unsafe or unlicensed type".
To cure this problem, download and install Build 4208 of Cardbox 3.0 from http://www.cardbox.com/downloading/updates.htm. For more information, see http://www.cardbox.com/support/clientHistory.htm.
If you ever need to check what build of Cardbox you are using, the command Help > About Cardbox will tell you.