I’ve spent this week immersed in all things Mavericks, reading through hundreds of user forum threads, installing Mavericks on Macs in my lab, and conducting a lot of R&D.

Although Mavericks has some interesting new bells and whistles, in my opinion none of them fit into the I-can’t-get-work-done-without it category.

So my answer to the question, should I upgrade to Mavericks, is NO… right now the potential benefits are completely overshadowed by the fact that this upgrade can cause countless problems.

Unless there is a specific reason, I always recommend against being a very early adopter of any new operating system. For those readers who are itching to start playing around with Mavericks, I would encourage you to wait until Apple releases at least two maintenance updates (OS X 10.9.2)… And even then I wouldn’t recommend you upgrade any critical or production Mac workstation to Mavericks… and if you do please make sure you have a backup you can revert to it, in the event things go horribly wrong!

Please read through my recent blog posts for more specifics, but here is a brief summary of my Mavericks observations so far… including things that are likely to affect an average Mac user:

  • One of the biggest problems with upgrading to Mavericks is software incompatibilities, especially with older software that starts up when the Mac is booted. This can cause Mavericks to run extremely slow or not boot properly. Culprits include: AntiVirus, third-party file sharing (like DropBox and Google Drive), third-party remote control, and system tweaks/add-ons. This can be extremely tricky to troubleshoot after upgrading.
  • If you are using Apple Mail as your email client, and have a large amount of stored email or have a fairly complex setup (like multiple email accounts or numerous custom rules), it is likely you will run into headaches with Mail after upgrading to Mavericks. There doesn’t seem to be a common cause for these issues, and they can typically be fixed using traditional troubleshooting methods, but they appear to be fairly widespread… and can take hours to fix.
  • If you are using Parallels or VMware Fusion to run a Windows VM, you will likely need to upgrade your software PRIOR to upgrading to Mavericks, otherwise your VM will not work. This will likely require paying for an upgrade.
  • Mavericks has a history of corrupting external hard drives. If you have one or more external drives connected to your Mac, it is critical that you check software and firmware prior to upgrading.
  • Printers, scanners, and other peripherals that worked fine will likely require updated drivers to function properly after upgrading to Mavericks, and it may take months for these drivers to be released (if at all). Every new version of OS X inevitably kills support for very old peripherals.
  • Macs that have a Promise Pegasus RAID should absolutely not be upgraded to Mavericks, not until Promise releases a fix for the problems being reported.
  • If you use Cisco AnyConnect for VPN, it will need to be updated prior upgrading to Mavericks, otherwise you won’t be able to VPN reliably.
  • Mac servers should not considered for a Mavericks upgrade, not until Apple fixes all the problems introduced by doing so.
  • Although theoretically you can upgrade a Mac running OS X 10.6.8 directly to Mavericks, in my opinion this is a very bad idea. Macs running Snow Leopard are typically booted into 32-bit mode, and Mavericks will only run in 64-bit mode. This means 32-bit applications like Cisco VPN Client will no longer work, nor will apps requiring Rosetta. Also Macs running Snow Leopard are far more likely to have old software installed, so the likelihood of EVERYTHING working with Mavericks is minimal.