iOS 15.4.1 ― Bug Fixes, Changes, and Improvements

[Rider3]

I found a similar issue but this was also there from 15.4 as well.

If I tried to update using itunes, it won't work, it will ask for my unlock code, then give error 4000. Last night I tried doing an update in recovery mode, at which point, it seemed to work but then when the phone rebooted, it got stuck at the apple logo. Not sure what happened but glad I have icloud backups, haha.

Have the same problem on a Win 10 PC. When it asks for the password and entering it shows the error code 4000, unable to update iPhone. It wouldn't update normally in iTunes without the error.
Downloaded the .ipsw 3 times, uninstalled iTunes, installed iTunes, no help. Had to update OTA.
This has occurred on the last two updates.

 

[sorgo †]

I found a similar issue but this was also there from 15.4 as well.

If I tried to update using itunes, it won't work, it will ask for my unlock code, then give error 4000. Last night I tried doing an update in recovery mode, at which point, it seemed to work but then when the phone rebooted, it got stuck at the apple logo. Not sure what happened but glad I have icloud backups, haha.

Have the same problem on a Win 10 PC. When it asks for the password and entering it shows the error code 4000, unable to update iPhone. It wouldn't update normally in iTunes without the error.
Downloaded the .ipsw 3 times, uninstalled iTunes, installed iTunes, no help. Had to update OTA.
This has occurred on the last two updates.

I was able to get around this “error 4000” by putting my iPhone into recovery mode and then updating using my trusty Surface Pro 2 on Windows 11 a couple of nights ago. Granted, it wasn’t a full restore, just a simple reinstallation “update” to the same version (15.4) that had previously been installed over the air. Everything completed successfully but that error is still rather annoying—and well-known, if a quick internet search is any indication.

 

[cigz]

Maybe this is the “fix” on battery drains in 15.4.1. But, mine didn’t notice visible difference with 15.4 (iPP M1 and iPhone 11), except (slightly) better battery drains when in use.

Exactly, i wouldn't be suprised if they changed how the promotion on iPhones worked so it's not draining battery and i'm pretty sure something changed with mine. It just doesn't feel as smooth as on 15.4

 

[jetsam]

Have the same problem on a Win 10 PC. When it asks for the password and entering it shows the error code 4000, unable to update iPhone. It wouldn't update normally in iTunes without the error.
Downloaded the .ipsw 3 times, uninstalled iTunes, installed iTunes, no help. Had to update OTA.
This has occurred on the last two updates.

I'm having the same issue. At one time this workaround worked - but no longer. I tried updating using iMazing, and that also failed, so I think the issue is not iTunes.

I gave up and am using OTA update, too. No problems there.

 

[Samdh90]

I was able to get around this “error 4000” by putting my iPhone into recovery mode and then updating using my trusty Surface Pro 2 on Windows 11 a couple of nights ago. Granted, it wasn’t a full restore, just a simple reinstallation “update” to the same version (15.4) that had previously been installed over the air. Everything completed successfully but that error is still rather annoying—and well-known, if a quick internet search is any indication.

I think it would have worked on my end but something got messed up. I know that normally using a recovery mode update will work in most cases. Oh well though, no harm done on my end

 

[atton]

I'm having the same issue. At one time this workaround worked - but no longer. I tried updating using iMazing, and that also failed, so I think the issue is not iTunes.

I gave up and am using OTA update, too. No problems there.

I was getting the same error on my desktop when I updated with the ipsw to 15.4 when it came out. I read somewhere it’s the iTunes version so I tried with my laptop that runs an earlier version or two of iTunes (not sure which one right now) and I was able to update to 15.4 as usual.

Haven’t tried 15.4.1 but I wouldn’t think the version of the update would matter.

 

[Rider3]

I'm having the same issue. At one time this workaround worked - but no longer. I tried updating using iMazing, and that also failed, so I think the issue is not iTunes.

I gave up and am using OTA update, too. No problems there.

I was able to update using the .ipsw by turning passcode off on iPhone. Worked as it should.
It removes any credit cards you have in Wallet, but just asks for the codes when you reinstall cards.

 

[Canyda]

I can't prove this was 15.4.1 per se, but given that it dropped this week .... some recent iOS update appears to have turned on cellular connectivity for EVERY APP ON MY iPHONE.

I was wondering why I was burning through so much data this week despite my iPhone being on wifi literally 90% of my day or more, and went into my settings and every app had cellular connectivity activated.

 

[Samdh90]

I was able to update using the .ipsw by turning passcode off on iPhone. Worked as it should.
It removes any credit cards you have in Wallet, but just asks for the codes when you reinstall cards.

Hi,

Thank you and I have read others were successful doing this but to remove the code, faceID, and any wallet items seems annoying. This is something that a user "should" not have to do in order to update using a PC, IMO.

 

[sorgo †]

Also for what it may be worth @Samdh90 @jetsam @Rider3 and as a final note on the subject, I was able to suss out from my little bit of research that the “full”/standalone version of iTunes is potentially better for avoiding or circumventing errors (such as #4000) compared to the Windows Store app. Not sure of such a claim’s validity but it may help someone.

P.S. I did receive the error on the standalone iTunes for Windows but again was able to successfully circumvent it and complete the installation through recovery mode.

 

[Motionblurrr]

To the people who are having the error '4000' on Windows, here's the fix (I did it yesterday)

Turn off passcode.

Set your screen dimming to never.

Plug in your iPhone and update via iTunes. Keep your screen on like on the homepage or something. And done!

 

[Rider3]

Hi,

Thank you and I have read others were successful doing this but to remove the code, faceID, and any wallet items seems annoying. This is something that a user "should" not have to do in order to update using a PC, IMO.

It doesn't effect FaceId. It retains that setting. I agree, user should not have to do this. Maybe an iTunes update will come soon.

 

[jetsam]

Also for what it may be worth @Samdh90 @jetsam @Rider3 and as a final note on the subject, I was able to suss out from my little bit of research that the “full”/standalone version of iTunes is potentially better for avoiding or circumventing errors (such as #4000) compared to the Windows Store app. Not sure of such a claim’s validity but it may help someone.

P.S. I did receive the error on the standalone iTunes for Windows but again was able to successfully circumvent it and complete the installation through recovery mode.

I also was using the version of iTunes downloaded directly from Apple. I never use apps from the Microsoft store if I can avoid it. I don't know what the problem is - but apps on the MS Store always seem worse than the same app directly downloaded - and I'm not just talking about Apple apps.

 

[jetsam]

I was getting the same error on my desktop when I updated with the ipsw to 15.4 when it came out. I read somewhere it’s the iTunes version so I tried with my laptop that runs an earlier version or two of iTunes (not sure which one right now) and I was able to update to 15.4 as usual.

Haven’t tried 15.4.1 but I wouldn’t think the version of the update would matter.

Do you think you could find out what version of iTunes you were using that worked? Apple has archived many old versions of iTunes here and I wouldn't mind giving an old version a try.

 

[AE14]

OK just to update, I signed out of my Apple ID to take any emails off of messages. I then rebooted and sign back in. Now it works. Speaking with apple was no help

 

[gwhizkids]

Wasn’t going to install this update (as I had the beta profile installed and didn’t want to have to uninstall/reinstall it to get this minor release). But, my desktop shortcut bookmarks weren’t functioning at all on 15.4 so I decided to see if 15.4.1 would fix it.

It did.

Right after I sent feedback to Apple about the issue.

 

[sbcdk]

To those of you fighting Error 4000.

The latest iTunes is broken. The 12.12.3.5 from March 9, 2022.

You need to uninstall and download the 12.12.2.2 from October 29, 2021 instead. Then all should work just fine.

Took me several hours to figure that out…

 

[Donga120]

Myself and a few others on here, are currently testing something out for Craig F on this exact subject, as I’ve been reassured both methods are identical to each other:

“When you OTA, the patching process results in a binary-identical OS volume to the one installed via ISPW — the system uses a “cryptographic seal” that actually ensures that the system won’t even boot if there’s any difference” - Craig F

Yet, we are seeing different results on devices straight after using the OTA and IPSW update methods.

Will hopefully be able to put this debate to bed soon, once Craig sees are findings. Will post back on the most current iOS forum when we know ??.

I’ve always used IPSW. Never had a single issue or have half the bugs everyone talks about.

 

[Pixels7]

To those of you fighting Error 4000.

The latest iTunes is broken. The 12.12.3.5 from March 9, 2022.

You need to uninstall and download the 12.12.2.2 from October 29, 2021 instead. Then all should work just fine.

Took me several hours to figure that out…

What also worked for me, disable passcode, then update to new iOS via iTunes and then you automatically get prompted to enable your passcode after updating. I am getting this error 4000 when I want to update my iPhone or iPad for two years already on my windows 10 laptop, on different iTunes versions, and temporarily disabling passcode always works.

edit: I now see someone else also wrote this.. I overlooked that post, time to go to sleep

 

[Pearsey]

I’ve always used IPSW. Never had a single issue or have half the bugs everyone talks about.

Yeah same. 👍🏼

 

[Pearsey]

Battery on this build… wow!

IP12

 

[ph.rei]

I feel like they changed something regarding ProMotion (on iPhones). I've got my 13PM on monday and it came with 15.3 but i immediately updated to 15.4 and i was amazed, i've never seen an iPhone being so smooth before but now with 15.4.1 it feels slower... It's not choppy by any means but it literally feels like it's always 60hz or 90hz max. I even turned on my 12 Pro with iOS 14.7 to compare and there's not much of a difference and when i limited refresh rate to 60hz, the animations on 13PM feel slighly worse than on my 12 Pro.
This is literally the first time i'm considering downgrading. I can live with worse battery life if it means the screen hits 120hz more often.

I feel the same. 60fps seems smoother on a 60fps phone compared to 13pro wit limited frame rate

 

[adrianlondon]

Yeah same. 👍🏼

Yeah not same 👍🏼

 

[Fred Zed]

Does hand over and iCloud tabs between devices work now? It hasn't between my MBP and iPhone for a while.

 

[TheYayAreaLiving 🎗️]

Does hand over and iCloud tabs between devices work now? It hasn't between my MBP and iPhone for a while.

Agree with this. My iCloud tabs stopped working too. It’s so annoying. They’re not updating and showing up on my iPhone, iPad, and MacBook Pro 🫥