Turn Off Java

Java doesn’t come as an out-of-the-box install on OS X Mountain Lion, but it will be installed automatically when an app needs it. Any app you install that needs Java will therefore install it the first time it runs, but this raises an issue: Java has persistently been proven to be a serious security risk.

One solution is to simply turn off Java unless you need it. To do this, open Java Preferences, which is in the Utilities folder of the Applications list of Finder, and then remove the check alongside Enable Apple Plug-In and Web Start Applications. Then remove the checks under the On heading in the list of Java SE engines installed on your system.

Should an app start that needs Java, you’ll be shown an error to the effect that Java isn’t installed. Simply repeat the previous steps in reverse and enable Java—but don’t forget to disable it again afterward!

You might also want to disable access to Java within Safari, bearing in mind this is a typical attack vector for malware. To do so, start Safari, start System Preferences (application menu→Preferences), and select the Security tab. Then remove the check alongside Enable Java.

Use a VIP Mailbox

Mail features a way of prioritizing email from certain people who you value above others—a feature Apple calls the VIP mailbox (short for Very Important People, of course).

The feature isn’t activated by default and can’t be found on any menu but is actually easy to set up.

Configuring VIP Mail

To activate the feature, you must first mark at least one person who sends you email as a VIP. To do this, select any email from the individual, and then click the empty star alongside their name in the mail, or right-click their name in the From field of an email and select Add to VIPs.

Once you do this, a new VIP mailbox will appear in the mailbox list sidebar and Favorites toolbar (if you have either visible—you can select to view either from the View menu). Selecting the new mailbox will cause your mail to be filtered so that only VIPs are visible, although you can also further filter the list of mails by selecting individual VIPs in the list that appears beneath.

Be Notified Only of VIP Mail

You can configure Mail so that you’re notified within Notification Center only of new VIP mail. To do so, open Mail’s Preferences dialog box (Mail→Preferences), and ensure the General tab is selected. Then select VIPs from the New Message Notifications drop-down list.

To return to being notified of all mail at a future date, repeat this step, but select Inbox Only from the drop-down list.

Deactivate the VIP Mailbox

To remove somebody from the VIP list, simply click once more the star alongside their name in an email, or right-click their name and click Remove from VIPs. To completely deactivate the VIP function, remove all VIPs in this way, and then quit and restart Mail.

See Your Mac’s Serial Number

To quickly view your computer’s unique serial number, as well as the build version of OS X (that is, the internal code used by Apple to track software releases), click the Apple menu, and then select About This Mac. In the window that appears, click Version several times (beneath the large “OS X”) to cycle through the available information.

You will almost certainly need your serial number if you phone Apple for technical support.