Windows 10: Unable to install Cumulative Update Preview for 21H1 KB5003690 on my desktop

So I have a Windows 10 custom build that I have been trying to get this update through for the bestt part of a month and a half. I have clean installed twice to no avail, it just gets stuck at "getting ready" and after a while it just goes "cleaning up" at 0% install and reverts . Any ideas as to why this is happening? I have secure boot running, and have no issues installing anything but this. Mind you I am running a clean install now after my RAM corrupted my last installation beyond recognition. SpecsMSI B450 Gaming Max Pro 32 gb Corsair Vengence LPX C16 4x8Ryzen 5 3600x Seagate Barracuda 2

:)

 

KB5003690 Windows 10 2004 19041.1081, 20H2 19042.1081, 21H1 19043.1081 Win Update

Welp, nothing blew up. *Smile














KB5003537 was a .NET Framework update.
KB5003742 came with KB5003690.

 

KB5003690 Windows 10 2004 19041.1081, 20H2 19042.1081, 21H1 19043.1081 Win Update

Done and dusted along with a BIOS Update that was also pending for my non-production machine: Asus RTX 2080Ti:

 

KB5003690 Windows 10 2004 19041.1081, 20H2 19042.1081, 21H1 19043.1081 Win Update

All appears ok except the RH. Really weird. 3 weeks till PT, see how it logs then. Thanks for the confirmation.