How to Update to iOS 15
Jak aktualizovat na iOS 15
iOS 15 Update Problem
Problémy s aktualizací iOS 15
How to Downgrade
Jak přejít na nižší verzi

Downgrade iOS 15: Jak to udělat bezpečně a snadno

• Připravte se na downgrade
• Jak přejít na nižší verzi iOS 15
• Výběr nástroje pro přechod na nižší verzi iOS 15
• Opravy problémů s přechodem na nižší verzi
• Časté dotazy k downgradu iOS 15

Část 1. Jste dobře připraveni na downgrade iOS 15?

Byla vydána nejnovější aktualizace iOS, ale uživatelé si již stěžují na některé její závady. Chcete-li tyto problémy překonat, můžete zvážit provedení downgradu iOS 15. Měli byste však udělat krok zpět a pochopit jeho důsledky. Například downgrade může vymazat všechna stávající data ve vašem telefonu, včetně vašich fotografií, aplikací, kontaktů atd. Proto je důležité přijmout potřebná opatření, než zrušíte aktualizaci iOS 15 na iPhone.

1.1 Proveďte zálohu zařízení

Toto je nejdůležitější věc, o kterou byste se měli postarat, než přejdete na nižší verzi iOS 15 na předchozí stabilní verzi. Když downgradujeme zařízení se systémem iOS, může to skončit smazáním všech dat v něm uložených. Od mediálních souborů po data aplikací – můžete skončit tím, že ztratíte veškerý stávající obsah v telefonu. Nejlepším způsobem, jak se naučit downgradovat z iOS 15 na stabilní verzi, je proto vytvoření zálohy telefonu. Tímto způsobem můžete po dokončení downgradu snadno získat zpět důležitá data obnovením jejich zálohy.
Zálohujte iDevice pomocí Dr.Fone
  • 1Připojte svůj iPhone nebo iPad k počítači.
  • 2Ručně vyberte typ dat nebo vyberte vše.
  • 3Kliknutím na tlačítko „Zálohovat“ zálohujete data zařízení lokálně.
Jedinečné vlastnosti:
  • •Zálohujte celé zařízení iOS, včetně jeho kontaktů, protokolů hovorů, zpráv, fotografií, videí atd.
  • •Zálohujte a obnovujte svá data z jednoho zařízení do druhého (nebo z jedné verze iOS do druhé) bez jakýchkoli problémů s kompatibilitou.
  • •Extrahujte existující zálohu iCloud nebo iTunes a obnovte ji na zařízení dle našeho výběru.
  • •Prohlédněte si data ze záložního souboru a selektivně je obnovte. Stávající data budou při obnově zálohy zachována.
Stažení Stažení

Zálohujte iDevice pomocí iTunes

  • 1Spusťte aktualizovanou verzi iTunes a připojte k ní zařízení iOS.
  • 2Přejděte na kartu „Souhrn“ a na kartě „Zálohy“ najděte příslušnou možnost.
  • 3Kliknutím na tlačítko „Zálohovat nyní“ uložíte zálohu svého zařízení.
Věci k poznámce:
  • •iTunes nemohou obnovit zálohu vyšší verze nižší verze. Před upgradem na iOS 15 si tedy musíte své zařízení zálohovat.
  • •Žádné ustanovení pro náhled dat a jejich selektivní obnovu.
  • •iTunes při obnově zálohy vymaže stávající data na vašem iPhone.
Získejte iTunes nyní

1.2 Pochopte časový limit pro downgrade iOS

Celý proces downgradu verze iOS je časově citlivý, což si mnoho uživatelů neuvědomuje. Promluvme si o tom podrobně.

  • Pokud máte nainstalovanou beta verzi iOS, můžete kdykoli downgradovat beta verzi iOS na předchozí stabilní verzi (dokud nebude vydána oficiální veřejná verze iOS).
  • Po vydání stabilní veřejné verze iOS máte pouze 14 dní na downgrade zařízení na předchozí existující verzi iOS.

1.3 Vyberte správnou verzi pro downgrade z iOS 15

V ideálním případě můžete pouze downgradovat iOS 15 na předchozí stabilní verzi. Pokud například chcete provést downgrade iOS 15, můžete se vrátit pouze k předchozí stabilní verzi, která je podepsána společností Apple. Můžete navštívit IPSW.me a zkontrolovat, zda je k dispozici kompatibilní firmware.

1.4 Vědět, jak přejít na verzi, která již není podepsána společností Apple (v případě potřeby)

Jak víte, pro downgrade iOS 15 musíte provést potřebné kroky do 14 dnů od jeho oficiálního vydání. Uživatelé se také mohou vrátit pouze k předchozí stabilní verzi. Pokud však uplynulo 14denní trvání a chcete přejít na verzi, která již není podepsána společností Apple, musíte použít nástroj třetí strany. S pomocí nástrojů, jako je TinyUmbrella nebo TaigOne Downgrader, můžete do zařízení nainstalovat jakoukoli podporovanou verzi iOS. Napodobují podpis společnosti Apple a umožňují nám nainstalovat personalizovaný firmware (verze pro iOS) na zařízení iDevices.

I když celý proces by byl docela technický a nemusel by přinést pozitivní výsledky. Vzhledem k tomu, že tyto nástroje třetích stran nejsou podporovány společností Apple, musíte k tomu provést útěk z vězení. To se nedoporučuje, protože to ovlivní záruku vašeho zařízení a vy byste již neměli přístup k oficiálním verzím iOS. Kromě toho bude vaše zařízení zranitelné vůči nechtěným bezpečnostním hrozbám.

Část 2. Jak bezpečně přejít na nižší verzi iOS 15?

Nyní, když jste si vědomi všech předpokladů pro downgrade iOS 15, můžete snadno splnit své požadavky. V ideálním případě můžete využít pomoc iTunes nebo jakéhokoli jiného nástroje třetí strany a naučit se, jak přejít na nižší verzi z iOS 15. V každém případě se předem ujistěte, že existuje záloha vašeho zařízení. Abychom vám to usnadnili, poskytli jsme dvě řešení pro přechod na nižší verzi iOS 15.

2.1 Řešení pro přechod na nižší verzi iOS 15 jedním kliknutím

Kroky k aktualizaci na iOS 15:
  • Připojte své iOS zařízení k PC a spusťte Dr.Fone.
  • Klikněte na modul „Opravit“ a přejděte na možnost Oprava iOS.
  • Vyberte jeden z režimů a potvrďte svou volbu výběrem zobrazené verze iOS a klikněte na „Start“.
  • Pohodlně se usaďte a chvíli počkejte, protože aplikace začne stahovat kompatibilní firmware pro vaše zařízení iOS.

    • Poznámka: Před přechodem na nižší verzi zkontrolujte na https://ipsw.me/product/iPhone , zda je k dispozici kompatibilní firmware.

drfone android box
Dr.Fone - Oprava systému (iOS)
  • Aktualizujte na iOS flashováním předchozího firmwaru.
  • Může také aktualizovat iOS na vašich iDevices.
  • Žádná závislost na iTunes.
  • Opravte všechny problémy se systémem iOS, jako je zamrznutí iOS, bílé logo Apple atd.
Získat pro PC Získat pro Mac

2.2 Přejděte na nižší verzi iOS 15 pomocí iTunes

Though, there are a lot of users who wish to take the assistance of iTunes to do the same. While you can perform iOS 15 downgrade with iTunes, it has its own cons. For instance, you might end up losing the existing data on your phone as it would restore your device to its factory settings. The process is also a bit technical, and you might end up damaging your device in the process.

What you need:
  • The latest version of iTunes
  • IPSW file you wish to install
Steps to downgrade iOS 15 with iTunes
  • Beforehand, Find my iPhone service on your device should be turned off. To do this, unlock it and go to its iCloud Settings > Find my iPhone to disable it. You need to enter your Apple ID and password to confirm this.
  • Now, connect your iOS device to the system and launch an updated version of iTunes on it. Click on the device icon and select your iPhone/iPad.
  • Go to its “Summary” tab and hold the Option Key (on Mac) or the Shift Key (on Windows) while clicking on the “Update” button.
  • This will open a browser window, letting you go to the location where the downloaded IPSW file is saved.
  • Select and load the IPSW file on iTunes and confirm your choice to forcefully update the connected device. Wait for a while and let iTunes complete the iOS 15 downgrade.
operate with itunes

Part 3. Best iOS 15 Downgrading Tools

As you can see, sometimes it can be tough to undo an iOS 15 update on iPhone or iPad. To make the entire process simpler, there are tons of third-party tools that you can try. Not only will they let you downgrade iOS version without losing data, but they would also yield better results. Also, if you have a jailbroken device, then you can even downgrade it to any previous iOS version. Let’s get to know more about the features and flexibility of some of these readily available tools.

3.1 Downgrading Tools for Common People (Fast & Easy to Use)

If you are a beginner and do not have a lot of technical knowledge about iOS downgrading, then consider picking either of the following tools.

3.2 Downgrading Tools for Tech-savvy Users (Complex But Can Achieve More)

If you want more flexibility with your device and have decent technical experience, then you can also explore some of these options too.

tips

What are SHSH blobs for iPhone?

Both SHSH and SHSH2 blobs are referred to digital signatures deployed by Apple on respective IPSW files. This protects the authenticity of the IPSW files and only signed software would be installed on the device. When Apple releases a new iOS version, it stops signing the previous version. In this way, users need to upgrade to the latest public iOS version. This is where previously saved SHSH blobs are used to forge these signatures in order to downgrade our devices.

Part 4. iOS 15 Downgrading Troubleshooting

4.1 iOS 15 Downgrade Failed Many Times

This is one of the most common issues that users face while downgrading their iOS devices. The chances are that while downgrading your device, the process would stop in between unexpectedly.

It happens when we try to downgrade the device to an incompatible iOS version. A faulty internet connection or low free space on the device can also trigger it.

Quick Fixes:
  • Check the iOS version: Needless to say, if you are trying to downgrade your device to an iOS version it no longer supports, then you might face unwanted issues. Ideally, you should try to downgrade iOS 15 to a previous version and not any other existing one.
  • Have a stable internet connection: An inconsistent internet connection is another prominent cause for this error. It happens when the download of the iOS update is halted in between (due to a poor connection). Therefore, make sure that the device stays connected to a working and fast internet connection for a seamless downgrading. You can go to your phone’s WiFi settings to further diagnose this.

4.2 iOS Stuck in Recovery/DFU Mode/Apple Logo

While downgrading your device, your phone might get stuck in the recovery mode, Apple logo, or the DFU mode screen. The situation might seem a bit tedious, but you can try to resolve it by forcefully restarting your phone in most of the cases.

Downgrading from an unstable version, the download process of the firmware update has been halted in between, or any other firmware related issue.

Quick Fixes:
  • Forcefully restart your device: By applying the correct key combinations, we can forcefully restart an iOS device and resolve this issue. Since it resets the current power cycle of the device, it is also known as a soft reset. If you own an iPhone 6s or an older generation phone, then long press the Power and Home button for at least 10 seconds. Users with an iPhone 7 or iPhone 7 Plus can press the Power and the Volume Down button. Keep pressing them until your phone restarts. For iPhone 8 and newer versions, you need to quick-press the Volume Up button first. Let it go and quick-press the Volume Down button. Subsequently, hold the Side button and let it go once the phone restarts.
  • Connect it to iTunes: In case if your phone is stuck in recovery or DFU mode, and you haven’t connected it to iTunes, then do the same. In no time, iTunes will automatically detect that your device is in the recovery mode and display the following prompt. Just confirm your choice and restore your device to factory settings to fix this.

4.3 iOS 15 Downgrade stuck on “Attempting data recovery”

The final step in the downgrading process is when the existing data on the device is recovered. Though, while doing so, the device might get stuck in the process and end up in the same loop.

An incompatible iOS version, loose connections, jailbroken device, lack of free storage, or any other related issue.

Quick Fixes:
  • Check whether your iPhone is jailbroken: Mostly, users get this error while performing iOS 15 downgrade on a jailbroken device. If your device is jailbroken, then you should not use iTunes to downgrade it. Instead, use a readily available tool like iFaith or TinyUmbrella to do the same.
  • Boot your iPhone in Recovery Mode: You can also take the assistance of iTunes and boot your device in the Recovery Mode to resolve this problem. To do this, just launch iTunes on your system and connect your phone to it. Now, using the correct key combinations, forcefully restart your device (already listed above). Subsequently, iTunes will detect as soon as your phone boots in the Recovery Mode. When you get the following prompt, click on the “Restore” button to reset your device.

4.4 iOS 15 Downgrade with iTunes won’t work

Most of the users take the assistance of iTunes (and an IPSW file) to downgrade iOS 15. Though, if there is a problem with the file, your device, or iTunes, then the process might not work.

An unsupported version of iTunes, corrupt IPSW file, or conflict with the device itself can result in this error.

Quick Fixes:
  • Check the IPSW file: Firstly, make sure that you have downloaded the correct IPSW file from a trusted source. Also, the IPSW file should be compatible with your iOS device else you might face this issue.
  • Disable Find my iPhone: Before you connect your device to iTunes, make sure that the Find my iPhone feature is disabled in it. To do this, go to its iCloud Settings > Find my iPhone and simply turn off this feature. This will not cause any conflict when you undo an iOS 15 update on iPhone.
  • Update iTunes: Needless to say, you should use an updated version of iTunes to downgrade iOS 15. Just launch iTunes on your system and go to Help > Check for Updates. This will make iTunes check for any available update. After finishing the update, you can restart your system and reconnect your device.

4.5 iPhone stuck in a loop trying to restore during downgrade

While restoring the device during the downgrading process, your device might get stuck. For instance, it can get stuck in a restart loop, not letting you access the device.

Lack of free space on the device, corrupt storage, incomplete update, bad IPSW file use, or any other compatibility issue.

Quick Fixes:
  • Force restart your device: This will reset the present power cycle of your device and will let you fix any minor issue related to it. To do this, you need to press certain keys on your device. We have already listed the correct key combinations to force restart a device in the previous sections.
  • Restart the process: If the downgrading process has been halted in between and your phone keeps restarting, then force restart it first. Now, connect it to iTunes or use any other third-party tool to undo an iOS 15 update on iPhone all over again.
  • Use a 3rd party tool: If nothing else seems to work, then consider using a dedicated iOS repairing tool like Dr.Fone - System Repair (iOS). It can fix all kinds of iOS and iTunes related issues without causing any harm to your device. Just launch the application and follow a simple click-through process to put your phone out of the loop and downgrade it to a stable iOS version.

4.6 iOS 15 Downgrade won’t work using SHSH

SHSH Blobs are Apple signatures that are needed to downgrade iOS 15 in a timely manner. Their absence or a wrong SHSH entity can tamper with the downgrading process.

Wrong SHSH blob, corrupt unit by a third-party dump, or an expired SHSH blob can be some of the major reasons for this.

Quick Fixes:
  • Use an SHSH blobs dumper: There are tons of readily available third-party SHSH dumpers (like iFaith) that you can try. Though, most of these applications will require a jailbroken device. You can simply connect your device or provide its model to obtain an ideal SHSH blob.
  • Obtain your device’s SHSH blob: You can connect your iPhone/iPad to the system and launch iTunes on it. Select your device and go to its Summary. Click on the “Serial Number” field a few times, till it displays the ECID number. Now, copy the ECID code and go to any online source to convert it into hexadecimal code.

4.7 Lost all data after iOS 15 Downgrade

This is one of the worst nightmares for any iOS user. After completing the downgrade, the chances are that you might end up losing all the saved photos, videos, contacts, messages, and other important files from your phone.

The process could be halted in between, a corrupt device, bad firmware, and so on. An upgrade to an unstable release of iOS can also cause data loss on your device.

Quick Fixes:
  • Use a data recovery tool ASAP: If you have suffered from an unwanted data loss on your device, then take the assistance of an iOS data recovery program . A part of the Dr.Fone toolkit, it is one of the first and the most successful data recovery tools for iOS devices. All you need to do is connect your device and launch the application. Follow a simple click-through process to extract all kinds of lost or deleted data from your device. The application will let you preview the extracted data, letting you selectively save it to the location of your choice.

4.8 Backup cannot be restored after iOS 15 downgrade

Even after losing their data while downgrading an iOS device, users try to restore an existing backup. Sadly, there are times when the previous iTunes or iCloud backup ceases to restore on the downgraded device.

The problem usually occurs due to a compatibility issue among various iOS versions. For instance, you could have taken the backup of your device when it was running on another iOS version and now you are trying to restore it on an unsupported iOS version.

Quick Fixes:
  • You can load a previous iTunes or iCloud backup using a iOS restoring tool and even preview its data on its interface. For instance, to restore an iCloud backup, you simply need to log-in to your iCloud account. The application will list the available backup files for you pick an ideal option. In this way, you can easily restore your data without erasing the existing content on your device.

Part 5. FAQs about iOS 15 Downgrade

Yes, you can downgrade iOS to a previous version signed by Apple. Users get 14 days after a public official release to do it. If you have upgraded your device to a version, then you can downgrade to a stable version easily (until 14 days after the release of its stable version).

There are all kinds of ways to undo an iOS 15 update on iPhone. If you want, you can take the assistance of iTunes to do the same. Though, to downgrade iOS 15 without losing data, consider using a more sophisticated tool like Dr.Fone - System Repair (iOS). In case if you have a jailbroken device, then you can even give tools like TinyUmbrella a go.

When we install an iOS version on the device, the Apple server asks for a digital signature to authenticate it. A signed IPSW file would have a verified signature issued by Apple, letting us upgrade/downgrade the device without any hassle. Therefore, if an IPSW file is not signed by Apple, then it will not be recognized by the server and the upgrading/downgrading process won’t be completed.

There are all kinds of SHSH dumps and readily available third-party tools that can help us force Apple’s signature and create SHSH blobs even after Apple stops signing them. Though, you should know that Apple might revoke the authentication of such SHSH blobs anytime. To do this, you need to have a jailbroken device and use a dedicated tool like iFaith or FutureRestore.

The Apple Software Program lets us test the releases of iOS before the public availability. You can join or leave the program anytime you want without spending anything. If you want to leave it, then go to the Unenroll section of the website.

apple beta program

Ideally, you can’t downgrade your device to an unsigned iOS version. This is because the Apple server won’t authenticate your downloading request without a valid SHSH blob. That is why users take the assistance of a previously saved SHSH blob to do the same. You can also use a third-party downgrading tool to do it as well.

After downgrading an iOS update, you might find an existing software profile on your device storage. To remove this, just go to your device’s Settings > General > Profile and select the iOS profile from here. Tap on the “Delete Profile” option and confirm your choice to remove it.

You can restore a previously stored SHSH blob from your device or forge Apple’s signature. There are a few third-party tools like FutureRestore that can help you do the same. You can also choose to dump your SHSH blobs in order to use them afterward. Though, in most of the cases, users have to jailbreak their device in order to do it.