Read This Before You Install OS X Yosemite (10.10.3) Public Beta

Dr. Mac’s Rants & Raves
Episode #113


While anecdotal evidence tells me that the current version of Mac OS X Yosemite (v10.10.2) is working pretty well for most users, Apple is already hard at work on the next update (v10.10.3), which includes a new photo manager and editor called Photos that replaces iPhoto.

Interest in the new Photos app is high and Apple recently opened up beta testing of version 10.10.3 to the public, so anyone with an Apple ID can join the fun ( and install the pre-release beta and the new Photos app.

It sounds tempting but my advice is: Don’t do it.

For heaven's sake... Please DO NOT install a beta OS before you read this column!

For most users, that’s the best advice I can offer. You see, the primary reason for beta testing is to uncover bugs and fix them before the product ships. Do you really want to install a buggy operating system on your main Mac?

Sigh. I was afraid of that. For those of you who feel obliged to try Photos, which requires the installation of OS X Yosemite 10.10.3 beta, here are some tips for survival:

  1. Do not — under any circumstances — install a beta version of OS X on a Mac you depend on for getting things done. Once you’ve installed a beta, it’s not terribly difficult to reinstall the previous release, but it’s time-consuming, a hassle, and there’s always the risk of data loss.
  2. Do not — under any circumstances — install a beta on your main hard drive. Apple recommends installing pre-release versions of OS X Yosemite on a secondary Mac, "since it may contain errors or inaccuracies." Personally, I think that’s overkill. You don’t really need two Macs, but you do need a second hard drive. That way, if something goes wrong, you just disconnect the beta drive and reboot from your usual startup disk.
  3. Back up your Mac and then back it up again, just in case. You can use Time Machine or any other backup software, but make a backup or two before you install the beta.
  4. Test your backup(s) to insure they work. This is a crucial but oft-overlooked step. First, check to make sure all the files you expect to find in your backup set are actually on the backup disk. Then, make sure those files are easily restored to your main hard drive.
  5. Last but not least, since the purpose of beta testing is to squash bugs, use the built-in Feedback Assistant to report any bugs you encounter.

Follow my advice and you can fearlessly check out the next version of OS X and its new Photos app. After beta testing software for more than 25 years, I’m positive most of you will be very unhappy if you ignore it.

And that's all he wrote...