[Thinkpad Tablet General] crgeek:
I am relatively new to flashing ROMs. I did have success with my old Nexus 6P. First I loaded Ubuntu Touch (clunky), then LineageOS 18 (poor performance), then LineageOS 17 (worked well), and finally Oreo 8.1 from eFoundation (completely degoogleized...works well). But then I decided to try LineageOS on my Lenovo Tab 4 8 (TB-8504F) and that didn’t go so well. Right now it will not shut down and all it will do is boot to fastboot mode. I can issue fastboot commands and boot into TWRP...I found 2 different versions of TWRP that apparently have been modified to work on the TB-8504 and tried both:

twrp-3.2.3-0-TB-8504x.img

twrp-3.3.1-1-TB8504.img

and I’ve tried 2 different versions of LineageOS

lineage-17.1-20210408-UNOFFICIAL-TB8504.zip

lineage-18.1-20220223-UNOFFICIAL-TB8504.zip

When I try to adb sideload one of these ROMs, TWRP gets stuck at

Patching system image unconditionally…

The attached images show the results of Advanced Wipe (system, cache, and data), Format Data, and ADB Sideload attempts.

After those failures I decided to try flashing a stock ROM using QFIL (yet another learning curve lol). I’ve only been able to find one stock ROM:

Lenovo_Tab_4_8_TB-8504F_USR_S001019_1909091114_Q12000_ROW_QPST

I have found several other links to stock ROMs but they pointed to non-existent pages or pages that said I wasn’t authorized to download. Here is the log I get when I try downloading in QFIL:

022-03-08 18:31:52.649 Start Download

2022-03-08 18:31:52.650 Program Path:C:\Users\xxxxxxxx\DeleteMe\LenovoTB-8504F\StockFlashingFiles\StockRom\Lenovo_Tab_4_8_TB-8504F_USR_S001019_1909091114_Q12000_ROW_QPST\Firmware\prog_emmc_firehose_8917_ddr.mbn

2022-03-08 18:31:52.652 ***** Working Folder:C:\Users\xxxxxxxx\AppData\Roaming\Qualcomm\QFIL\COMPORT_3

2022-03-08 18:33:22.708 Binary build date: Jun 25 2019 @ 03:16:15

2022-03-08 18:33:22.709 QSAHARASERVER CALLED LIKE THIS: 'C:\Program Files (x86)\Qualcomm\QPST\bin\QSaharaServer.ex'Current working dir: C:\Users\xxxxxxxx\AppData\Roaming\Qualcomm\QFIL\COMPORT_3

2022-03-08 18:33:22.709 Sahara mappings:

2022-03-08 18:33:22.710 2: amss.mbn

2022-03-08 18:33:22.711 6: apps.mbn

2022-03-08 18:33:22.712 8: dsp1.mbn

2022-03-08 18:33:22.713 10: dbl.mbn

2022-03-08 18:33:22.713 11: osbl.mbn

2022-03-08 18:33:22.714 12: dsp2.mbn

2022-03-08 18:33:22.715 16: efs1.mbn

2022-03-08 18:33:22.716 17: efs2.mbn

2022-03-08 18:33:22.716 20: efs3.mbn

2022-03-08 18:33:22.718 21: sbl1.mbn

2022-03-08 18:33:22.719 22: sbl2.mbn

2022-03-08 18:33:22.720 23: rpm.mbn

2022-03-08 18:33:22.720 25: tz.mbn

2022-03-08 18:33:22.721 28: dsp3.mbn

2022-03-08 18:33:22.722 29: acdb.mbn

2022-03-08 18:33:22.723 30: wdt.mbn

2022-03-08 18:33:22.723 31: mba.mbn

2022-03-08 18:33:22.724 13: C:\Users\xxxxxxxx\DeleteMe\LenovoTB-8504F\StockFlashingFiles\StockRom\Lenovo_Tab_4_8_TB-8504F_USR_S001019_1909091114_Q12000_ROW_QPST\Firmware\prog_emmc_firehose_8917_ddr.mbn

2022-03-08 18:33:22.725

2022-03-08 18:33:22.726 18:33:22: ERROR: function: sahara_rx_data:276 Unable to read packet header. Only read 0 bytes.

2022-03-08 18:33:22.728

2022-03-08 18:33:22.729 18:33:22: ERROR: function: sahara_main:982 Sahara protocol error

2022-03-08 18:33:22.730

2022-03-08 18:33:22.730 18:33:22: ERROR: function: main:320 Uploading Image using Sahara protocol failed

2022-03-08 18:33:22.731

2022-03-08 18:33:22.732

2022-03-08 18:33:22.733 Download Fail:Sahara Fail:QSaharaServer Fail:Process fail

2022-03-08 18:33:22.733 Finish Download

I've also attached this log as a text file, thinking that may be easier to read .

Any help resolving this would be greatly appreciated!

Thanks,

Rich