FAQ: Microsoft rents out Office 365

It's no different than a magazine, which would prefer to sell subscriptions rather than single copies from a newsstand (if the latter even exist these days).

Or think about it this way: Each time Microsoft rolls out a new Office, it has to once again convince customers to plunk down their money. Not so with subscribers, who simply download a new version when it's released.

I'm not biting. But I may want the new Office. What are my options? You can buy one of the three retail perpetual-licensed versions of Office 2013 for Windows:

Office Home and Student 2013 includes Excel, OneNote, PowerPoint and Word; It can be installed on one PC and costs $139.99.

Office Home and Business 2013 includes the above applications, plus Outlook; It can be installed on one PC and runs $219.99.

Finally, Office Professional 2013 includes the applications in Home & Student, as well as Access, Outlook and Publisher; It can be installed on one PC and costs $399.99. (Office Professional is the same suite as is installed when you subscribe to Office 365 Home Premium or Office 365 University.)

I'd like to try out Office 365. Can I do that without paying? Yes. Microsoft offers a 30-day free trial to Office 365 Home Premium (but not University). You must provide a credit card, however, which will be automatically billed at the end of the trial unless you cancel the deal before the 30 days are up.

Anything else I should know about Office 365? Microsoft has made some noise about how it will update Office for subscribers more frequently than it has perpetual licenses in the past, but it's not provided any details of the timing, much less what those upgrades may include.

Take that with a grain of salt: Windows customers with semi-long memories may remember Vista Ultimate, a top-of-the-line edition that Microsoft promised would receive regular updates with exclusive new features. Instead, Microsoft stiffed Ultimate owners -- who complained that they received little they'd been promised -- and then quietly discarded the concept.

I've been running the free preview of Office 365 Home Premium. What do I do if I want to convert to a subscription? Microsoft says you must uninstall the Office 2013 apps from your Windows machine. Yes, we know that's a pain, but it's what Microsoft says.

It's unclear whether your customization settings will be retained after you've reinstalled Office 2013 from the paying subscription. We're guessing not.

Gregg Keizer covers Microsoft, security issues, Apple, Web browsers and general technology breaking news for Computerworld. Follow Gregg on Twitter at  @gkeizer, on Google+ or subscribe to Gregg's RSS feed . His email address is gkeizer@computerworld.com.

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