"Error occured" in Windows Update 0x80070643
Solution 1:
How do I fix the Windows Update error?
First:
Run the Windows 10 Update Troubleshooter
Windows 10 update troubleshooter
From an Admin Command Prompt:
net stop bits
net stop wuauserv
net stop cryptsvc
ren %systemroot%\softwaredistribution softwaredistribution.bak
ren %systemroot%\system32\catroot2 catroot2.bak
net start bits
Restart and test updates
Also temporarily remove third party anti virus software
Restart and test updates.
These are the main points. There are more tests including hardware tests in the article.
But start as above and see if the Update function returns
Next:
If these steps do not work, it might be best to run a Windows 10 Repair Install.
https://www.microsoft.com/en-us/software-download/windows10
Windows 10 is running, so click on the Download button (not Upgrade Button) and select Run.
This will launch the Repair and proceed normally.
Start with the option to keep everything.