Windows 10 Home 2004 (build 19041.572) - Downloading updates fails with 0x800703e6

[ipostdog]

I think this issue was caused by the "get 20h2 features on 2004" regedit hack I did a while ago (I have reverted it)
SFC says "Windows Resource Protection could not start the repair service."
SFCFix output:
SFCFix version 3.0.2.1 by niemiro. Start time: 2021-08-17 13:30:46.624 Microsoft Windows 10 Build 19041 - amd64 Not using a script file. AutoAnalysis:: SUMMARY: No corruptions were detected. AutoAnalysis:: directive completed successfully. Successfully processed all directives. SFCFix version 3.0.2.1 by niemiro has completed. Currently storing 0 datablocks. Finish time: 2021-08-17 13:31:05.146 ----------------------EOF-----------------------
CBS log is attached.