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Q&A: MacFixIt Answers

We answer Mac-related questions about Java and Flashback vulnerabilities, and more.

MacFixIt Answers is a feature in which we answer questions e-mailed in by our readers.

This week people wrote in with questions on how the Java vulnerabilities and Flashback malware seen on OS X might affect Linux systems and older versions of OS X, how to set up Time Machine to work with networked volumes, and the options for showing invisible characters when composing word processing documents in OS X. We welcome alternative approaches and views from readers, so if you have any suggestions, post them in the comments!

Question: Setting up Time Machine on any networked volume
MacFixIt reader Stuart asks:

I would like to know how to set up Time Machine on a NAS network-attached storage or any type of network?

To use Time Machine with unsupported network volume setups, you will need to open the Terminal and run the following command:

defaults write TMShowUnsupportedNetworkVolumes 1

After doing this, and with the NAS formatted and available via AFP (Apple Filing Protocol--the native file sharing protocol for Mac systems) on the network, open the Time Machine preferences and the shared drive should appear.

Question: Threat of Flashback-like attacks on Linux
MacFixIt reader Sky asks:

Hi, I run Linux systems, but Java is used in the browsers such as Firefox and SeaMonkey. Is [the recent Flashback malware] something that I need to pay attention to also?


The Java vulnerability is universal and will affect all platforms that support Java; however, this current Flashback malware is targeted to OS X systems. Nevertheless, be sure to update Java on your system to the latest version so the hole in it that allowed for this malware to work on OS X will not be taken advantage of for Linux or any other OS you use. You can get the latest version from the Java Web site.

Question: Java vulnerabilities on older OS X systems
MacFixIt reader Michael asks:

While I run MacOS 10.6.8 and have the Java Preferences application in /Applications/Utilities, what about the older systems that can't upgrade? There's some concern for these machines that can't run the 10.6 Java patch recently released from Apple.

Will the instructions in your article on how to check for and disable Java work for older versions of Mac OS X?

In older versions of OS X you should still be able to use the Java Preferences to disable the Java runtimes. The screenshot in that article of the Java Preferences was taken from a machine running OS X 10.5, and you can uncheck both of the runtimes listed to disable Java.

Alternatively you can remove the JavaVM framework as well, which should also break the Java installation, though only do this if you do not use any programs that require Java.

Question: Showing invisible characters in OS X
MacFixIt reader Elizabeth asks:

In a previous version of Mac OS X, possibly Tiger, I used Command-; to show invisible formatting such as "space" or "end-of-line." Do you know how I can do this in Snow Leopard?

This feature will depend on the program you are using. It will be available in some, and not in others, and the controls for enabling them may change in different versions of the programs. For instance, in Apple's Pages program you can press Shift-Command-I to show invisible characters, but in Word 2011 you will need to click the "show nonprinted characters" option in the tool bar.

Questions? Comments? Have a fix? Post them below or e-mail us!
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