This was the answer I finally received from Apple Support, if you consider it an answer.
Most issues encountered with .Mac Syncing can be resolved by resetting the sync information on .Mac. This reset should always be done from the computer with the current information.
Before resetting or deleting any data, you should back up any current data you wish to keep. For more information about how to back up your important data, please see the following Apple Care Support article:
How to back up and restore your important Mac OS X 10.4 files
<http://www.info.apple.com/kbnum/n301239>
Please make sure your computer has been updated to Mac OS X v10.4.3. For more information about this update, please see the following article:
Mac OS X Update 10.4.3
<http://www.apple.com/support/downloads/macosxupdate1043.html>
Second, you should verify that you can connect to you iDisk. If you are unable to connect to you iDisk using your university's network, you will be unable to sync.
Connect to your Remote iDisk in this way:
1. Click Go in the Finder menu bar
2. Choose iDisk > My iDisk
If you have successfully connected to your iDisk, then proceed to the steps below.
To reset sync information:
1. Make sure you are connected to the Internet.
2. Open System Preferences and click .Mac.
3. Click Advanced and then click Reset Sync Data.
4. Choose the information you wish to reset from the Replace pop-up menu (such as Bookmarks, Keychains, or All Sync Info).
5. Click the right arrow. The screen will change to say "On .Mac with sync info from this computer".
6. Click Replace. This will replace the information on .Mac with the information from your computer.
If .Mac Bookmarks or .Mac Address Book do not behave correctly after resetting your .Mac syncing information, you should reset their syncing preferences. The .Mac sync reset must be done immediately prior to this. If you haven't just done so, reset your sync information as shown above then proceed.
Reset .Mac Bookmarks
1. Go to .Mac <http://www.mac.com/> and log in.
2. Click Bookmarks and then click Open Bookmarks.
3. Click Preferences.
4. Deselect the "Turn on Bookmarks Synchronization" checkbox.
5. Click Save.
6. Click Preferences again, and reselect the checkbox.
7. Click Save.
Reset .Mac Address Book
1. Go to .Mac <http://www.mac.com> and log in.
2. Click Address Book.
3. Click Preferences.
4. Deselect "Turn on .Mac Address Book Synchronization" checkbox.
5. Click Save.
6. Open Preferences again, and reselect the checkbox.
7. Click Save.
Note that syncing does not display iCal data on the .Mac website. Use iCal's publishing feature to publish calendars to the web. See iCal Help under the Help menu in iCal for more information.
If you are unable to successfully synchronize your data with .Mac Sync in Mac OS X v10.4, you may need to completely reset sync data on all computers and on .Mac.
1. Unregister all computers using a computer with Mac OS X v10.4.
2. For the initial sync, register only one computer running Mac OS X v10.4 and sync only one data type (Bookmarks, Calendars, Contacts, Keychains, or Mail settings).
3. Repeat using only one data type at a time until all syncs are successful, or until you find the affected data type.
After you have identified the data type that prevents a successful sync, please provide us with the following information:
- If the affected data type is an Address Book contact, how many total contacts are you attempting to sync?
- If the affected data type is a Safari bookmark, how many total bookmarks are you attempting to sync?
- If the affected data type is an iCal calendar, how many total calendars are you attempting to sync and how many events are in each calendar?
- When you installed Mac OS X v10.4, did you perform an Erase and Install, Archive and Install, or Upgrade a previous version of Mac OS X?
- A detailed outline of your network. For example: hubs, switches, routers, proxy servers, firewalls, AirPort Base Stations, and 3rd-Party Wireless routers.
- Internet service provider (ISP)
- Does this issue occur on other computers within your network?
- Does this issue occur with your computer on a different network?
- Does this issue occur on a different computer within a different network?
- When was the last time this worked?
- What hardware or software changes have occurred since this last worked?
Sometimes I wish I was more of a geek than I am. At least then I'd feel like I knew what the heck they were talking about and feel more comfortable taking these steps without worrying about losing all my data.
eMac Mac OS X (10.4.3) PowerBook G4