iPhone 13 Pro update fails: Error 100, insufficient space

Hi everyone,


I’m trying to update/revive my iPhone 13 Pro, but it keeps failing with:


- AMRestoreErrorDomain error 100

- Restore Checkpoint Fingerprint: 06A6.0064

- failed to install splat

- install_splat / Cryptex1,SystemOS


The device is currently detected by Apple Configurator as:


- deviceType: iPhone14,2

- bootedState: Restore

- isRestorable: true

- pairingAllowed: false

- isPaired: false


I have already tried:


- macOS is up to date

- Apple Configurator revive

- Finder/Updater update path

- signed IPSW only

- official Apple cable

- direct connection, no USB hub

- Recovery mode

- I have not intentionally selected Erase/Restore yet because I’m trying to preserve data


The most important part of the log seems to be this:


text ramrod_splat_install: Installing Cryptex1,SystemOS -> /mnt9/cryptex1/current/os.dmg Transfer: Receiving 2013265920 bytes, writing 5236588544 bytes Transfer: Failed preallocation of 5236588544 bytes for /mnt9/cryptex1/current/os.dmg Transfer: Failed preallocation due to space. No hope in this succeeding, bailing. ramrod_splat_install: install handler failed CHECKPOINT FAILURE:(FAILURE:100) [0x06A6] install_splat Restore Checkpoint Fingerprint: 06A6.0064


Earlier in the same log, the update path says:


text requested restore behavior: Update Found variant: Customer Upgrade Install (IPSW)


So this was an update attempt, not an intentional erase/restore.


My questions:


1. Has anyone successfully recovered from Error 100 / 06A6.0064 / failed to install splat without erasing the iPhone?

2. Would DFU + Apple Configurator “Revive Device” have a real chance of preserving data in this specific case?

3. Is this more likely caused by low iPhone storage, APFS/container corruption, Cryptex/SystemOS install failure, or NAND/storage failure?

4. Is there any known way to free space or complete the update while the device is stuck in Restore mode?

5. If the log says “Failed preallocation due to space,” is Restore/Erase the only realistic solution?


I’m trying to avoid data loss if possible. Any advice from people who have seen this exact checkpo

Posted on Jun 1, 2026 7:10 AM

Reply
2 replies

Jun 1, 2026 8:57 AM in response to eakanat

ChatGPT says:


"""That message indicates that Apple Configurator was trying to install a Cryptex/SystemOS image during a restore or revive operation, but the iPhone ran out of available storage space in the temporary restore partition.


Key lines from the log:

Installing Cryptex1,SystemOS

Receiving 2013265920 bytes, writing 5236588544 bytes

Failed preallocation of 5236588544 bytes

Failed preallocation due to space

No hope in this succeeding, bailing

CHECKPOINT FAILURE:(FAILURE:100)

[0x06A6]


What it means:

  • Cryptex1/SystemOS is a special system image used by modern versions of iOS during updates, restores, and security-related operations.
  • Apple Configurator received a file of about 2 GB, but needed approximately 5.2 GB of free space when unpacked and written.
  • The restore environment on the iPhone could not reserve that space.
  • The process aborted at restore checkpoint 06A6.


Common causes include:

  1. Insufficient free storage on the iPhone
    1. The device may be nearly full.
    2. This is common when attempting an update rather than a full erase-and-restore.
  2. Corrupted APFS container or partition layout
    1. Storage exists but cannot be allocated correctly.
  3. Interrupted or failed previous update
    1. Temporary restore files may not have been cleaned up.
  4. System storage corruption
    1. The restore environment cannot mount or expand the Cryptex image properly.

What to try

If the iPhone still boots:

  1. Check available storage in Settings → General → iPhone Storage.
  2. Free at least 10–15 GB.
  3. Restart the iPhone.
  4. Retry the update.



If you are using Apple Configurator to recover the device:

  1. Put the iPhone into Recovery Mode or DFU Mode.
  2. Choose Restore rather than Update/Revive if you have a backup.
    • Restore completely erases the device and recreates the storage layout.
    • This often succeeds when an Update or Revive fails with space-related errors.


If Restore also fails:

  • Try a different USB-C/Lightning cable.
  • Update macOS and Apple Configurator.
  • Try the restore from the Finder app instead of Configurator.
  • Run the restore from another Mac if available.


The checkpoint code 06A6.0064 is consistent with a failure while installing the Cryptex/SystemOS image rather than a communication problem between the Mac and iPhone. The most significant clue in your log is:


Failed preallocation due to space


which points primarily to a storage allocation problem on the iPhone’s internal flash storage or its restore partition."""


Jun 1, 2026 8:54 AM in response to eakanat

eakanat wrote:
- AMRestoreErrorDomain error 100
- Restore Checkpoint Fingerprint: 06A6.0064
- failed to install splat
- install_splat / Cryptex1,SystemOS
The most important part of the log seems to be this:
text ramrod_splat_install: Installing Cryptex1,SystemOS -> /mnt9/cryptex1/current/os.dmg Transfer: Receiving 2013265920 bytes, writing 5236588544 bytes Transfer: Failed preallocation of 5236588544 bytes for /mnt9/cryptex1/current/os.dmg Transfer: Failed preallocation due to space. No hope in this succeeding, bailing. ramrod_splat_install: install handler failed CHECKPOINT FAILURE:(FAILURE:100) [0x06A6] install_splat Restore Checkpoint Fingerprint: 06A6.0064

Where are you seeing all these? Is your iPhone jailbroken? Are you using any unauthorised apps from the internet?





iPhone 13 Pro update fails: Error 100, insufficient space

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