One of the possible errors that a Windows 10 user may encounter is the message «Update definition for Windows Defender KB_NUM_RESOLUTION — error 0x80070643» in the update center. In this case, as a rule, other Windows 10 updates are installed normally.
To manually install the latest Windows Defender definitions from the Microsoft website
The first and simplest method that usually helps with error 0x80070643 in this case is to download the definitions of Windows Defender from the Microsoft website and install them manually.
To do this, follow these simple steps.
Go to https://www.microsoft.com/en-us/wdsi/definitions and go to the Manually download and install the definitions section.
In the «Windows Defender Antivirus for Windows 10» section, select the download in the required bit depth. Download definitions Windows Defender
After downloading, run the downloaded file, and after the installation (which can visually pass «quietly» without the installation windows appear) go to the Windows Defender Security Center — Protection from viruses and threats — Security updates and see the version of the threat definition. Installed version of Windows defender definitions
As a result, all the necessary updates to the definition for Windows Defender will be installed.