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This. Agreed, that's a good step. One more tip: if you have any external drives or USB sticks plugged in, unplug those too before trying again.

Yeah, that's a common headache. One extra thing to try is clearing your TPM from the BIOS, as that can sometimes force Windows to re-recognize the Secure Boot state. Hope that helps.

This. I had the same problem. Even with 8GB, it failed until I ran the Windows Update troubleshooter and cleared out the SoftwareDistribution folder.

+1 Yeah, that's a smart move. I'd also double-check that your external drive has enough free space for everything you need.

Yeah, agreed. Also double-check that TPM 2.0 is enabled in the BIOS, not just present—that one trips up a lot of people.