Microsoft has fixed the KB5048239 bug which wouldn't stop installing as it has been replaced it with the new KB5050411 update.
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Microsoft's KB5048239 Windows 10 update won't stop installing, possible workaround available [Update]
The troublesome KB5048239 update is back again and it is causing issues on Windows 10 PCs. According to reports, the update won't stop installing.
The infamous "0x80070643 - ERROR_INSTALL_FAILURE" issue is back with one of the new Windows 10 updates KB5048239. Thankfully, there is a fix.
It's one of those rare occasions when Microsoft released dynamic updates for Windows 10 in addition to the ones for Windows 11 that we covered earlier.