It looks like the first update for Windows 10 version 20H2 (KB4580364) has arrived with some issues. The hotfix for OS versions 19041.610 and 19042.610 not only causes an error resulting in loss of user certificates, but also issues when updating Microsoft Office applications.
The problem of the certificate, as such, is really serious. Remember that, at least in Spain, applying for a certificate involves some bureaucracy. The user must reapply for the certificate and go to a public administration office to verify their identity. After that, you will have to go through the process of downloading the certificate.
A new issue with update KB4580364
However, we must remember that update KB4580364 is presented as an optional fix. Therefore, the decision to install on Windows 10 or, in business environments, the corporate IT administrator is the user’s responsibility. On this occasion, many users have encountered a failure while updating the Microsoft Office suite.
After installing the update on Windows 10 October 2020 Update, users start seeing the error “Office 365 file download failed, error =”. As we can see, the message is not very descriptive because it doesn’t even display the error code. The issue affects corporate environments where Configuration Manager and Memcm are used to download updates.
This issue affects both Windows 10 and Windows Server 2019 after installing update KB4580364. Microsoft is investigating the problem to provide a workaround. For now, as engineer David James points out, the only remedy is to uninstall the patch, update Microsoft Office, and reapply the operating system update.
Microsoft recommends that you avoid updating via USB drives, DVDs, or ISO files and waiting for the update to be offered through Windows Update. Keep in mind that Windows 10 version 2004 still has security support, so there is no need to upgrade to Windows 10 version 20H2 as soon as possible.