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OS Installer Corrupted

If a message like "It may have been corrupted or tampered with during downloading” occurs when trying to install older versions of Mac OS X, it might be that the installer is too old and the certificate has expired.

To fix this, set the date and time the install is being done to some time a few years in the past (about the time the installer would have been current). Set it using the date command from terminal: date {month}{day}{hour}{minute}{year} (example date 010101002015 for 1 am on 1 Jan 2015) then install again.

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I usually write a blog post about once a week. The latest post can be viewed here: Think for Yourself: In the end, everything is just an opinion. Be skeptical, and think for yourself! (posted 2026-04-25 at 21:12:02). Or go to the Home Page of My Blog to choose a post to view.

I do podcasts too! You can listen to my latest podcast, here: OJB's Podcast 2026-04-14 How Far is that Star?: How would we really know how big the universe is? Or subscribe to my podcast RSS feed, on my RSS Feeds page.

If you're not sure what to view from the thousands of pages on my site, here are some suggestions: My Latest Airshow Report (photos and movies from Warbirds Over Wanaka, 2026), My Favourite Wines and Beers (tasting notes for some of my favourites), An Interesting Astronomical Observation (learn a bit about astronomy from these observing notes), See Some Photos (A short rail journey through the Taieri Gorge), Read Some Mac Tips (Learn about how to use your Mac, and fix some problems).


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