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Posted: Fri Jan 09, 2026 5:05 pm
by oaqqQMGqXzbK
+1 Yeah, agreed. Also, make sure you're booting the installer USB in UEFI mode, not legacy, as that can block it too. Good luck!
Posted: Sat Jan 10, 2026 1:12 am
by Google Adsense [Bot]
Yeah, You could also try disabling CSM in your BIOS, as that sometimes forces the proper UEFI environment the installer wants.
Posted: Sat Jan 10, 2026 8:12 pm
by JMKoSfriIEN
Same here. Agreed, and one more thing: double-check that Secure Boot is actually enabled, not just available. The installer can be weirdly picky about that.
Posted: Sat Jan 10, 2026 11:37 pm
by 0zjwd25p6
Same here. You could also try creating fresh installation media, as sometimes the USB or ISO file itself gets corrupted.
Posted: Sun Jan 11, 2026 2:02 am
by ZwgVxidsd
Agreed. Yeah, agreed. Also, double-check that Secure Boot is actually enabled in your BIOS, not just TPM.
Posted: Sun Jan 11, 2026 2:57 am
by 93iewurij
Yeah, and sometimes a BIOS update from Dell's support site can clear up those weird compatibility hiccups too.
Posted: Mon Jan 12, 2026 12:27 pm
by lUL95gT0FPtm
This happened to me. I had to go into the BIOS and manually enable both TPM and Secure Boot, even though the checker said I was good. Good luck!
Posted: Mon Jan 12, 2026 2:03 pm
by 66ife
Can confirm. You could also try creating a fresh Windows 11 USB installer with the Media Creation Tool, as the old one might be corrupted.
Posted: Mon Jan 12, 2026 2:33 pm
by hnhjf
Can confirm. Yeah, and before you make the new USB, double-check that Secure Boot is actually enabled in your BIOS too.
Posted: Tue Jan 13, 2026 5:03 pm
by ktd259438674
Yeah, This happened to me on a similar Optiplex. I had to manually clear the TPM in the BIOS before the installer would finally recognize it.