How to check a Mac’s OS upgrade history in System Profiler<article>
<section class="page">
<p>While macOS upgrades should always proceed in a sequential fashion, sometimes things go awry. Typically, the Software Update preference pane shows all updates available for your current release of macOS, and when installed, they disappear from the list.</p><p>However, I recently had a crash during an update that left me confused as to whether a security fix was installed or (based on errors) the whole thing had gone pear-shaped. Software Update showed no outstanding items to install, but I wanted to be sure.</p><p>Fortunately, there’s a way to review your system upgrade history, though you may have never needed to dig it up before:</p><ol>
<li>
<p>Hold down Option while choosing the menu and select
System Information.</p><p class="jumpTag"><a href="/article/3600312/how-to-check-a-macs-os-upgrade-history-in-system-profiler.html#jump">To read this article in full, please click here[/url]</p></section></article>
Source:
How to check a Mac’s OS upgrade history in System Profiler