MP 1,1-5,1 How should I Upgrade from Windows 11 23H2 to 25H2 in my MacPro 5,1 with OCLP

[Enricote]

I am using OpenCore Legacy Patcher OCLP 2.4.1 running Sequoia 15.7.2 and UEFI Windows 11 23H2.
I installed Windows 11 in UEFI mode following this OCLP guide:

Installing Windows in UEFI Mode | OpenCore Legacy Patcher

I wonder if I could upgrade to 25H2 just creating a Windows 11 Installation Media following the steps in this general guide:

I don´t want to brick my beloved 15 y. old Mac Pro….!

Thank you in advance!

 

[Enricote]

After some research I have taken the risk.
The guide worked perfectly well in my MacPro 5,1 so I have upgraded my original UEFI Windows 11 23H2 to the latest 25H2 without doing a fresh install. That process has been very straight and all files and drivers were kept in place. Windows 25H2 runs perfectly well.

"Windows Update" just was updating inside the original 2023 installation (23H2) because MacPro is an unsupported device. In two years, I had missed 24H2 and 25H2 versions.

I hope this can be useful for someone

 

[tsialex]

After some research I have taken the risk.
The guide worked perfectly well in my MacPro 5,1 so I have upgraded my original UEFI Windows 11 23H2 to the latest 25H2 without doing a fresh install. That process has been very straight and all files and drivers were kept in place. Windows 25H2 runs perfectly well.

When I need to upgrade Windows 10 installs to a Mac or PC that does not meet the arbritary requirements of Windows 11 SecureBoot/TPM2.0, but still have a CPU with the required instruction sets (SSE4.2/POPCNT, basically anything Nehalen forward), I prefer to use FlyOOBE (ex-Flyby11).

Btw just to add here for future searches - MacPro3,1 can only run Windows 11 up to 23H2. 24H2/25H2 will not work since MacPro3,1 CPUs do not have support for SSE4.2/POPCNT instructions.

"Windows Update" just was updating inside the original 2023 installation (23H2) because MacPro is an unsupported device. In two years, I had missed 24H2 and 25H2 versions.

Yes, but if you already have 24H2 fully updated is just a matter of running the Windows 11 25H2 Enablement Package (eKB).

Direct Link of x64 kb5054156 from Microsoft Updates catalog:

https://catalog.sf.dl.delivery.mp.microsoft.com/filestreamingservice/files/fa84cc49-18b2-4c26-b389-90c96e6ae0d2/public/windows11.0-kb5054156-x64_a0c1638cbcf4cf33dbe9a5bef69db374b4786974.msu