Apple Stops Signing iOS 18.0.1 - MacRumors
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Apple Stops Signing iOS 18.0.1

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Apple today stopped signing iOS 18.0.1, preventing iPhone users who have upgraded to iOS 18.1 from downgrading to iOS 18. Apple released iOS 18.1 a week ago on October 28.

Generic iOS 18
It is not unusual for Apple to stop signing older versions of iOS shortly after a new version of iOS is released. When Apple stops signing an update, it can no longer be installed on an iPhone due to a server-side software verification check that happens before new software is installed, so those who have upgraded to the latest version of iOS 18 cannot downgrade to iOS 18.0.1.

Apple prevents downgrading to older versions of iOS to encourage iPhone users to keep their operating systems up to date with the latest security fixes.

The iOS 18.1 update added the first Apple Intelligence features, including Writing Tools, a new look for Siri, summaries and smart replies, and more. Apple CEO Tim Cook recently said that iPhone users are upgrading to iOS 18.1 twice as fast as iOS 17.1 during the same timeframe last year.

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Top Rated Comments

S
SebCohen
24 months ago
I THINK I’ll wait for 18.2…not that long anyway and I’ve already got ChatGPT+ and Siri is like my demented half sister who always shows up high on crack at the family reunions and can’t tell us how she got there.

Jokes aside, there’s not REALLY that much difference anyway. Not any meaningful day to day differences. It’s iOS 17 with a sprinkle of Android…so far. What I’m saying is, it doesn’t hurt the slightest to wait a month.
Score: 4 Votes (Like | Disagree)
O.N.Y.X Avatar
O.N.Y.X
24 months ago

A pity. My “upgrade” to iOS 18 was a complete waste. RCS doesn’t work well and I don’t care about AI. I now have both turned off - and it’ll stay that way. What a disappointment.
Reading this, I’m super glad I decided not to „upgrade“ to iOS 18 months ago. With most of the features restricted to devices running U.S. English in the USA that upgrade would bring new bugs and likely make my iPhone 14 Pro a bit slower. So thanks but no thanks. 17.7 working fine here.
Score: 4 Votes (Like | Disagree)
frozencarbonite Avatar
frozencarbonite
24 months ago
As long as I can keep getting major security updates, I'm sticking with 17.7. I'd love to try 18.1, but it's not worth risking the irreversible problems it could cause.
Score: 2 Votes (Like | Disagree)
O.N.Y.X Avatar
O.N.Y.X
24 months ago

Does this mean if you’re still on 17.6.1 and want to go to 17.7 or 17.7.1 you can’t? Ie it will only allow updates to 18.1? (AFAIK anything that supported 17 supports 18)
No, you can update iOS 17 to its latest version. If you upgrade to iOS 18.x you can’t go back anymore.
Score: 1 Votes (Like | Disagree)
Populus Avatar
Populus
24 months ago
Good riddance (to 18.0.1, I mean).
Score: 1 Votes (Like | Disagree)
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