Microsoft has released a patch for it's Jet Database engine which is a core component of the Zone4 Software.  This patch fixes an issue which was affecting several critical functions in Zone4.  Zone4 users who where affected by this bug may have seen messages like: "The Category Name you have given to this category already belongs to another category.  Please give each category a unique name."  See below for a detailed description of this bug.
    To download the patch for this bug please use the Microsoft Windows Update Service by clicking here: http://v4.windowsupdate.microsoft.com/en/default.asp  This service scans your computer and notifies you of all Microsoft updates available for your system.  If you already have this update installed it will not be listed as an available update.  This particular patch is not considered a Critical Update and so it is listed in the Recommended Update section.  This patch is called Update for Jet 4.0 Service Pack 8 (KB829558).
    The Windows Update Service allows you to download and install this update by just clicking on it and proceeding through the installation instructions.
    For more Microsoft information about this update including direct download links to the patch please see here: http://support.microsoft.com/default.aspx?kbid=239114
    For more information from Microsoft about this bug please read here: http://support.microsoft.com/default.aspx?kbid=291162
Zone4 detailed description:  This bug affected Microsoft Access (Jet) databases (the race files) by allowing them to loose track of the autonumber id field values. What this means is that when you add a new record to a table it re-uses an ID number to identify the record. Now because this ID number must always be unique (a primary requirement for any database system), this bug causes problems for procedures trying to access the record using this identifier.  This basically corrupted the race files or corrupted the ability to add new records (racers, times, categories, etc)  There is no workaround in Zone4 for this issue and only a special process using Microsoft Access could repair an affected file.  If anyone has an affected file that they need repairing please contact Zone4 as the Microsoft patch will only stop this problem from happening again.