Another warning: Don't convert your Time Machine volume from HFS+ to APFS<article>
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<p>Months after the release of macOS 10.13 High Sierra, folks are still having problems with limitations of the new
Apple File System (APFS) format required for SSDs that run High Sierra, and which you can optionally upgrade other drives to use. That includes your columnist,
who biffed a Time Machine question that’s now updated for accuracy.</p><p>Time Machine can work with APFS volumes, but the shape looks like this:</p><p class="jumpTag"><a href="/article/3252819/storage/dont-convert-your-time-machine-volume-from-hfs-to-apfs.html#jump">To read this article in full, please click here[/url]</p></section></article>
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Another warning: Don't convert your Time Machine volume from HFS+ to APFS