Not to beat a dead horse, but I'm now having the exact same problem. According to the App Store, I was able to get to the Mountain Lion download on Sep 2, 2013.
Whose bright idea was to put OS X downloads on the App Store anyway... Grrrrrrrrr...
Plus the installed seems to delete itself when its done. I thought I kept a copy around for this eventuality, but I guess not.
Did anyone ever get a resolution to this?
If you're having problems with the App Store you might try this:
1 - enable the Debug menu in App Store:
- open the Terminal application.
- copy the command below and paste into the Terminal window:
defaults write com.apple.appstore ShowDebugMenu -bool true
followed by Enter.
- launch App Store, login.
2 - select the Debug ➙ Reset Application option:
3 - try again.
Thanks for the reply Mr. Toad!
Unfortunately, it made no difference
Fortunately, for me anyway, I found the copy of the Mountain Lion installer I had squirrelled away for just this kind of contingency.
In any case it would be much better if:
- The App Store would download the installer and/or
- It gave a more informative message.
In any case, it doesn't make Apple/App Store look very good. What do people do who support multiple Macs who can't/won't upgrade to the latest version.
Makes ya wonder...
Thanks again for your reply!