 
            ✗ This firmware is not signed. This means you cannot restore to it in iTunes.
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Download (5.24 GB)✗ This firmware is not signed. This means you cannot restore to it in iTunes. The instructions below are included for reference only.
iPhone_4.0_64bit_15.5_19F77_Restore.ipsw file that you downloaded.iPhone_4.0_64bit_15.5_19F77_Restore.ipsw file that you downloaded.cd ~/Downloadsidevicerestore -e iPhone_4.0_64bit_15.5_19F77_Restore.ipsw and press enter.cd DownloadsGet-FileHash iPhone_4.0_64bit_15.5_19F77_Restore.ipsw -Algorithm SHA12b0ebdd8a3a0f848970597f45ce5fb3ea7ffaf82. If it doesn't, you may need to redownload the file.cd ~/Downloadsopenssl sha1 iPhone_4.0_64bit_15.5_19F77_Restore.ipsw2b0ebdd8a3a0f848970597f45ce5fb3ea7ffaf82. If it doesn't, you may need to redownload the file.cd ~/Downloadsopenssl sha1 iPhone_4.0_64bit_15.5_19F77_Restore.ipsw2b0ebdd8a3a0f848970597f45ce5fb3ea7ffaf82. If it doesn't, you may need to redownload the file.| SHA256sum | 0a8ed259e3e7ef435ff79c3285f1aea36af48d5bedbf5c3a7c1444ba701e7bcb | 
|---|---|
| MD5sum | d091f4d51113a47de5978d0bf6edf227 | 
| SHA1sum | 2b0ebdd8a3a0f848970597f45ce5fb3ea7ffaf82 | 
iOS 15.5 includes the following improvements and bug fixes:
Wallet now enables Apple Cash customers to send and request money from their Apple Cash card
Apple Podcasts includes a new setting to limit episodes stored on your iPhone and automatically delete older ones
Fixes an issue where home automations, triggered by people arriving or leaving, may fail
Some features may not be available for all regions or on all Apple devices. For information on the security content of Apple software updates, please visit this website:
https://support.apple.com/kb/HT201222