Error 64 when flashing OpenGapps One Gapps (pico and nano) errors with 64 when I try to install using twrp-3.3.1.4. I know I'm using the right version. I'm on a brand new One Plus 7 Pro.

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Open GApps nano 9.0 - 20191017

- Mounting  /vendor

find: /system/system: No such file or directory
ls: /system/system: No such file or directory
- Gathering device &amp; ROM information

***** Incompatible Device Detected *****

This Open GApps package cannot be
installed on this device's architecture.
Please download the correct version for
your device: arm

******* GApps Installation failed *******

- Copying Log to /sdcard

- NO changes were made to your device

Installer will now exit...

Error Code: 64
cp: can't stat '': No such file or directory
ls: /system/system: No such file or directory
cp: can't stat '/system/system/etc/g.prop': No such file or directory
cp: can't stat '/system/system/default.prop': No such file or directory
cp: can't stat '/system/system/build.prop': No such file or directory
cp: can't stat '/vendor/vendor/build.prop': No such file or directory
cp: can't stat '/data/local.prop': No such file or directory
cp: can't stat '/build.prop': No such file or directory
cp: can't stat '/system/system/addon.d/70-gapps.sh': No such file or directory
cp: can't stat '/cache/recovery/log': No such file or directory
__bionic_open_tzdata: couldn't find any tzdata when looking for CST6CDT,M3.2.0,M11.1.0!
__bionic_open_tzdata: couldn't find any tzdata when looking for posixrules!
- Unmounting  /vendor

Updater process ended with ERROR: 64
I:Install took 9 second(s).
Error installing zip file '/sdcard/open_gapps-arm64-9.0-nano-20191017.zip'
Updating partition details...
I:Data backup size is 0MB, free: 227550MB.
I:Unable to mount '/usbstorage'
I:Actual block device: '', current file system: 'vfat'
...done
I:Set page: 'flash_done'
I:operation_end - status=1
I:TWFunc::Set_Brightness: Setting brightness control to 5
I:TWFunc::Set_Brightness: Setting brightness control to 0
I found that if upon receiving this error, before booting into LineageOS I can


Boot into the bootloader from TWRP,


Click on Reboot
Click on Bootloader

Boot into a new TWRP from the bootloader


Run twrp boot ./twrp.*.img

I can then install the gapps.




What cause this? Well my theory now is that the instructions on the Lineage OS suggest Wiping the System partition


  
  Now tap Wipe.
  Now tap Format Data and continue with the formatting process. This will remove encryption and delete all files stored in the internal storage.
  Return to the previous menu and tap Advanced Wipe, then select the System partition and then Swipe to Wipe.
  


I was doing that and it was working for the purposes of installing LineageOS, but I believe after the Advanced Wipe on the System Partition something wasn't working. It's as if the wipe was complete and LineageOS could be installed, but mounting the partition after the install of LineageOS required rebooting into the recovery again. If you allow LineageOS to boot up before you flash GApps all bets are off. Worse this was the only way for it to work because if I rebooted into the recovery I would get the LineageOS recovery -- LineageOS now replaces TWRP entirely. I may have been able to install GApps from the LineageOS recovery's ADB Sideload option, but  rebooting into TWPR recovery by proxy of the bootloader worked too.