Trouble restoring ical from external hard drive

[susancpv]

Hi. I just had a new hard drive installed on my Mac Mini. The technician backed up by computer to an external hard drive, and I am having great difficulty restoring my ical to my computer. When I try Revert to Backup, the events are all grayed out and I can't access them. I have also tried dragging and dropping and clicking on each event, but nothing happens. Any hints?

Thanks. Susan