Click the Sync icon ( ) to the right of your iDisk icon in the Finder sidebar to initiate a manual sync.
If that does not resolve the issue, you should troubleshoot iDisk syncing. Make sure you back up any files that only exist on your iDisk. If a file only exists on your local iDisk copy, be sure to drag a copy of it to your desktop or another location off iDisk prior to any troubleshooting. If a file you are expecting to see no longer appears on your iDisk, see iDisk Sync: Data unexpectedly appears to be missing from your iDisk.
Follow these steps to troubleshoot your iDisk, verifying each one and stopping if you resolve the issue: