Apple has issued an update for its Mail e-mail client program in OS X Mavericks. The update addresses a number of outstanding bugs that have been affecting users who have installed the new OS, specifically involving managing messages in Gmail accounts. In addition, the update fixes problems with inaccurate unread message counts.
This update is likely a welcome one for those experiencing these problems, but Apple does issue a few words of caution for those who are eager to install the update.
First, as with any software update, Apple recommends you make a full backup of your system, preferably using Time Machine, but you can also use a system cloning tool if you have one. In addition Apple warns rather generally that this update may have unexpected results if you have third-party software installed that affects it or the operating system. Examples of such software could be third-party spam filters and plug-ins for Mail and related services, even firewalls that might interfere with network connections that Mail is trying to make.
While for the most part third-party software isn't likely to stop working, it is possible, so if you experience problems after installing the update, that's one place to check.
After installing the update and relaunching the program, Mail may update your inboxes or show a Welcome to Mail screen; then you should be able to access your messages again.
The Mail update is available through Apple's Software Update service, which can be accessed in the Apple menu in OS X Mavericks. The update can also be downloaded and applied manually from the Mail Update for Mavericks support Web page.