The KB4048955 update for Windows introduced some quality improvements and other elements that claimed to resolve security vulnerabilities. However, a bug caused error 0x80070643 to pop up every time the users tried to install the update. Error 0x80070643 is a general Windows Update installation error code that can appear on your computer screen during installation.
What does 0x80070643 mean?
Windows Error code 0x80070643 is an error caused during installation. It may be caused by a server-side problem and you may retry the installation or check the internet connection. Try restarting the computer after running the Windows Update Troubleshooter.
What do I do if Windows Update failed to install?
If Windows Update failed to install, you may try again to install it. Delete Temporary Files and Browser Cache. If that doesn’t work, manually resetting Windows Update Components to default. A few more solutions would be to run SFC and DISM, or the Windows Update Troubleshooter.
Fix Windows Update error 0x80070643
Here’s what you can do to fix the issue in Windows 10 or Windows 11:
1] Rename the SoftwareDistribution folder
Error 0x80070643 can either stop you from installing Windows update or installing another software. This issue may occur either due to the corruption of the MSI software update registration or if the .NET Framework installation on the computer has become corrupted.
To solve this, it is advisable to rename the SoftwareDistribution folder. To rename the Software Distribution folder, open an elevated command prompt windows, type the following commands one after the other, and hit Enter:
net stop wuauserv
net stop bits
rename c:\windows\SoftwareDistribution SoftwareDistribution.bak
net start wuauserv
net start bits
Next clear the contents of the Catroot2 folder.
2] Clear Catroot2 folder contents
Catroot and Catroot2 are the some of the important Windows OS folders which are required while Windows Updates process. So, if you are facing the problem while updating your Windows and receiving error message – 0x80070643, then reset the Catroot2 folder.
To reset the catroot2 folder do this:
Open an elevated Command Prompt, type the following command one after the other and hit Enter:
net stop cryptsvc
xcopy %systemroot%\system32\catroot2 %systemroot%\system32\catroot2.old /s
Next, delete all the contents of the catroot2 folder.
Having done this, in the CMD windows, type the following and hit Enter:
net start cryptsvc
Your catroot folder will be reset, once you start Windows Update again.
3] Run Windows Update Troubleshooter
Occasionally, when Windows users try to install the latest updates from Windows Update, they sometimes receive an error message – 0x80070643. The Windows Update Troubleshooter resolves many of these errors so run it and see.
4] Install Windows Updates in Clean Boot State
It is a good idea to install Windows Updates in Clean Boot State, since all non-Microsoft processes & Services do no start in that state and so there can be no 3rd-party interferences causing Windows Update to fail.
All the best!