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Trying to install windows 8.1 on an MSI gs73vr 6rf. Fresh install goes well as do drivers and such. Problems begin when using windows update and trying to install .net 3.5 or any updates at all. I can use an offline updater but windows update will not work nor can I install the aforementioned .net framework. I have installed the recommended updates, ran the update repair, DISM and sfc all to no avail. Is it a BIOS thing? At a loss.