Q&A: MacFixIt Answers

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

This week, readers wrote in with questions about battery care, where to get Mac-specific training, what to do about guest accounts deleting user data, and the limitations of using an iMac as an external display for other systems. I welcome views from readers, so if you have any suggestions or alternative approaches to these problems, please post them in the comments!

Question: Common battery care guidelines
MacFixIt reader Thomas asks:

I am eternally confused by battery care. My current understanding is that the old NiCad batteries lived longer/worked better if you used them up before recharging, to avoid the memory effect. Newer Lithium ion batteries, like in an iPhone, do not work this way, and the recommendation I'd heard was that to keep them fully charged was the ideal. The advice in this article [on battery health] sounds like the old NiCad thing. Can you clarify my confusion?

Answer:
While I am not a battery engineer and perhaps cannot answer in the detail you need, all types of battery will lose capacity over time. I am not versed in whether or not the specific "dead spot" issues you are referring to in nickel cadmium batteries are mirrored directly in other types; however, regardless of the reason for reduced capacity, it is true that not using a battery at all or storing a battery either too full or too empty will cause it to lose capacity at a greater rate.

For some reason, as Apple outlines on its Web site, it is best to continually use a lithium ion battery at a steady rate that is equivalent to running through a complete charge cycle at least every month or two, and store it half-full.

Question: Getting Mac-specific training
MacFixIt reader Darrel asks:

After being a Windows guy for over 15 years I would like to know where you suggest getting the equivalent training to be an "expert"-level Mac person.

Answer:
If you are looking for official training, then Apple offers a number of courses and programs for becoming a certified Apple technician, or simply to get familiar with its products for your own uses. There's information about these on Apple's Training Web site.

Beyond this, the more common approach is to explore around, try things, make backups, and be willing to accept failure and restore from backups if needed. There are some great online communities such as the Apple discussion forums where many quite knowledgeable people can can help you get going.

Question: Guest account deleting files on logout or reboot
MacFixIt reader cmitchell asks:

I have an iMac running 10.8.2. I set up a guest account for my daughter and every time I restart or reboot all her data, music gets deleted. Is there any way to prevent this?

Answer:
This is the nature of the guest account. It is there for temporary use so people can use a system without their changes affecting it. To set up a permanent account, create one for her in the Users & Groups system preferences. In here you can create a managed or "standard" account, or an admin one that has the permissions needed to make changes such as installing applications and system settings.

Question: Using an iMac as a display with an older system
MacFixIt reader Tim asks:

I want to connect my MacBook Pro (2009) to my 27-inch iMac (early 2012) so I can use the iMac as a larger display for editing. My MacBook has a Mini DisplayPort and the iMac has a Thunderbolt connection. Can I connect the two and will that work to show the output of the MacBook on my iMac? If so, do I just need to buy a Mini DisplayPort-to-Thunderbolt cable?

Answer:
While this technically should work, Target Display Mode is supported only for systems that have Thunderbolt connections, so such a setup would require a MacBook from 2011 or later.

Questions? Comments? Have a fix? Post them below or e-mail us!
Be sure to check us out on Twitter and the CNET Mac forums.