Possibly there are other references for this topic, and my Google-fu was weak this morning. Nevertheless, it took me a while to figure out, and if this saves someone else a minor panic, so much the better.
The scenario: I needed to re-download the Mac OS X Lion installer from the App Store. In tinkering with that interface, I unthinkingly clicked the X button on Lion’s entry in the Purchases window. Bam! No more Lion.
A couple of entries suggested things that might restore it, but none did. In the end, the procedure was simple.
- Select Store > View My Account and sign in.
- Look for a section headed iTunes in the Cloud, with a Hidden Purchases entry, and click View Hidden Purchases.
- Click Unhide for those purchases you wish to appear in your App Store Purchases window, then click Done.