How to Fix iTunes Error 1601 When Restoring iPhone

By ErrorFix · Updated October 26, 2026 · 8 min read

What error 1601 means

Error 1601 appears in iTunes on Windows or Finder on a Mac while you are restoring an iPhone. The dialog says the iPhone could not be restored and that an unknown error occurred (1601), and the phone is left waiting for a restore that never got properly started — often showing the cable-and-computer screen or a completely black display. Your data is not confirmed gone, but the restore cannot proceed until the underlying mode or firmware problem is corrected.

The code itself gives the clue. Error 1601 sits in the 1600 range of iTunes errors, a family tied to the firmware-flash phase of a restore. Where neighbouring codes fail at other points of that phase, 1601 usually means the restore could not even get the phone into the expected restore mode: the phone is in recovery mode when DFU mode is required, a custom firmware file is being offered without the matching prepared DFU state, or the computer-side software is too old to run the DFU handshake. Retrying the same restore from the same mode with the same file fails the same way until the mode or the file is fixed.

The fix is almost always on the computer side and within your control. Enter DFU mode with the correct button sequence for your iPhone model, switch to official firmware if you were using a custom file, clean up the USB connection, update iTunes, and download a fresh firmware image — and error 1601 almost always resolves at one of those steps.

Common causes

• Phone not in DFU mode: the phone sits in recovery mode while the restore expects DFU, so iTunes cannot start the firmware flash.
• Custom firmware without the matching DFU state: a modified IPSW is rejected because it was not restored from the specially prepared DFU state it requires.
• Corrupted or invalid firmware file: a half-downloaded IPSW, or a file for the wrong iPhone model, fails validation before flashing.
• Outdated iTunes or macOS: old software mishandles the DFU restore handshake and aborts with 1601.
• Bad USB connection: a worn or uncertified cable, a USB hub, or an unstable port breaks the low-level transfer.
• Security software or a stale hosts entry: antivirus, firewall tools, or a leftover gs.apple.com redirect interrupts verification.

How to fix error 1601 — step by step

Follow these in order. Error 1601 is a restore-mode failure, so the first step — entering real DFU mode — clears many cases on its own, and the second step — switching to official firmware — clears the custom-firmware cases. The later steps clean up the computer side, and the fresh firmware restore at the end is the fallback that almost always works.

1. Enter DFU mode with the correct button sequence. Error 1601 very often means iTunes or Finder could not get the phone into the restore mode it needs, so start by entering DFU mode deliberately rather than relying on recovery mode. On iPhone 8 and later: connect the phone to the computer, press and quickly release Volume Up, press and quickly release Volume Down, then press and hold the Side button until the screen goes black — then hold Side and Volume Down together for five seconds, release Side, and keep holding Volume Down until the computer detects a device. The screen stays black in DFU mode; an Apple logo or a cable-and-computer graphic means you are in recovery mode instead. On iPhone 7 or 7 Plus: hold Side and Volume Down together for eight seconds, release Side, and keep holding Volume Down. On iPhone 6s and earlier: hold Home and Sleep together for eight seconds, release Sleep, and keep holding Home. Once the computer detects the phone with a black screen, click Restore.
2. Restore official firmware if you were using a custom IPSW. Error 1601 is closely tied to custom firmware: a modified IPSW will only restore from a specially prepared DFU state, and a normal restore attempt with a custom file fails with 1601. Unless you have a specific reason to use custom firmware, abandon it for this restore. Put the phone into DFU mode as above, click Restore in iTunes or Finder, and let the computer download and install the official, signed firmware for your exact iPhone model. If you must use a custom file, it has to be restored from the matching prepared DFU state, and any mismatch will bring 1601 straight back.
3. Clean up the USB connection. A weak link between the computer and the phone can stop the restore-mode handshake that error 1601 is tied to. Use a genuine Apple cable or a certified MFi cable, plug it directly into a USB port on the computer itself — no hubs, docks, or keyboard pass-throughs — and try a different port, preferably a USB 2.0 port. Unplug every other USB device for the duration of the restore, then try again from DFU mode.
4. Update iTunes, Finder, and the computer. Older iTunes builds and older macOS versions handle the DFU restore handshake poorly, and error 1601 is a frequent result. In classic iTunes on Windows, click Help at the top of the window and choose Check for Updates; if you use Apple's modern apps, open the Microsoft Store, go to Library, and update Apple Music and Apple Devices. On a Mac, restores run through Finder, so install pending macOS updates from System Settings, General, Software Update. Restart the computer after updating, then retry the restore from DFU mode.
5. Delete the cached firmware and download a fresh copy. A half-downloaded or damaged IPSW sitting on the computer can keep producing error 1601 even when DFU mode is entered correctly. On Windows, remove the IPSW files from %AppData%\Apple Computer\iTunes\iPhone Software Updates; on a Mac, delete them from ~/Library/iTunes/iPhone Software Updates. Then put the iPhone back into DFU mode, click Restore, and let the computer download a clean, official firmware image. This erases the phone, so have an iCloud or computer backup ready to restore from afterward.
6. Disable security software, check the hosts file, and try another computer. Antivirus and firewall programs can block the low-level traffic between the computer and a phone in DFU mode, so on Windows open Windows Security, go to Virus and threat protection, and pause real-time protection for the restore attempt, making sure Apple Mobile Device Service is allowed through the firewall; turn everything back on when the restore finishes. Also check the hosts file for a leftover gs.apple.com redirect from jailbreak or downgrade tools: on Windows, open Notepad as an administrator and open C:\Windows\System32\drivers\etc\hosts; on a Mac, open Terminal and edit /etc/hosts. Delete or comment out any line mentioning gs.apple.com, save, and restart. If 1601 still survives all of this, try the restore on a second computer with current iTunes or Finder.

Did this fix it? Quick checklist

• iPhone entered DFU mode correctly: black screen, computer detects the device
• Official firmware being restored, not a custom IPSW without the matching DFU state
• Genuine or certified cable, direct USB port, iTunes or macOS updated
• Restore completes in DFU mode with freshly downloaded firmware — no error 1601

If error 1601 survives DFU mode, official firmware, a clean USB chain, updated software, fresh firmware, and a second computer, the phone's own flash hardware may be at fault. Book an Apple Store or authorized service appointment and mention error 1601 so they know the restore is failing before the flash begins.