iCal syncing is one of the handy features available in iCloud, Apple's cloud-based service. It was also available in MobileMe, Apple's previous cloud service. By syncing your calendars, you were assured that any Mac you used on a regular basis would always have all of your calendar events available to you. This is handy if you use multiple Macs at home or in the office, but it's especially handy if you take a mobile Mac on the road. When you update your iCal app on one Mac, the new entries are available on all of your Macs.
With the advent of iCloud, you can continue iCal syncing just by upgrading to the new service. But if you have an older Mac, or you don't want to update your OS to Lion or later (the minimum version of OS X required to run iCloud), then you may think you're out of luck.
Well, you're not. With a few minutes of your time and Apple's Terminal app, you can continue to sync iCal with multiple Macs.
What You Need
- Two or more Macs.
- OS X Leopard (10.5.x) or later. I believe these instructions will work for earlier versions of OS X, but I haven't been able to test them. If you decide to try this with an earlier version of OS X, please let us know how it goes.
- A cloud-based storage service. The instructions in this guide are for Dropbox. Other cloud services may work as well, but we have only tested Dropbox.
- A few minutes for each Mac you wish to sync.
Let's Get Started
- Install Dropbox, if you're not already using it. You can find instructions in the Setting Up Dropbox for the Mac guide.
- Open a Finder window and navigate to your home folder/Library. Replace "home folder" with your user name. For example, if your user name is tnelson, the full path would be /Users/tnelson/Library. You can also find the Library folder by clicking on your user name in a Finder sidebar.
A note for Lion users: Apple hid the users Library folder in Lion. You can make it visible with these tricks: OS X Lion Is Hiding Your Library Folder.
- Once you have the Library folder open in a Finder window, right-click the Calendars folder and select "Duplicate" from the pop-up menu.
- The Finder will create a duplicate of the Calendars folder and name it "Calendars copy." We created the duplicate to serve as a backup, since the next steps will remove the Calendars folder from your Mac. If something goes wrong, we can rename the "Calendars copy" folder back to Calendars, and be right back where we started.
- In another Finder window, open your Dropbox folder.
- Drag the Calendars folder to the Dropbox folder.
- Wait for the Dropbox service to finish copying the data to the cloud. You'll know when it's finished by the green check mark that appears in the Calendars folder icon in the Dropbox folder.
- Now that we have moved the Calendars folder, we need to tell iCal and the Finder its new location. We do this by creating a symbolic link from the old location to the new one.
- Launch Terminal, located at /Applications/Utilities/.
- Enter the following command into Terminal:
- ln -s ~/Dropbox/Calendars/ ~/Library/Calendars
- You can check that the symbolic link was created correctly by launching iCal. All of your appointments and events should still be listed in the app.
Syncing Multiple Macs
Now that we have your main Mac synced with the Calendars folder in Dropbox, it's time to get the rest of your Macs up to speed by telling them where to look for the Calendars folder.
To do this, we're going to repeat all of the above steps except one. We don't want to drag the Calendars folders on the remaining Macs to the Dropbox folder; instead, we want to delete the Calendars folders. Don't worry; we'll still create a duplicate of each folder first.
So, the process should look like this:
- Perform steps 1 through 4.
- Drag the Calendars folder to the trash.
- Performs steps 9 through 12.
That's it; all of your iCal apps are now synced.
One additional note. Because you are syncing all of your Macs against one Calendars folder, you may see a message about an incorrect iCal account password, or a server error. This can happen when the source Calendars folder had data for an account that isn't present on one or more of your other Macs. The solution is to update the account information for the iCal app on each Mac, to make sure they're all the same. To edit the Account information, launch iCal and select Preferences from the iCal menu. Click the Accounts icon, and add the missing account(s).