My problem is that it is impossible to install the update KB280522. Update for .NET Framework 4.5 for Windows 8, Windows RT and Windows Server 2012 - KB2805222 I tried with h**p://windows.microsoft.com/es-419/windows-8/windows-update-error-0x800f081f DISM.exe / online / cleanup-image / scanhealth This indicates that you can reparare me. DISM.exe / online / cleanup-image / restorehealth This tells me error because I can not find the source. I tried with DISM.exe / online / cleanup-image / restorehealth / Source: G: \ sources \ sxs but keeps telling me it can not find the source. I tried himself with Dism / online / enable-feature / featurename: NetFx3 / All / Source: G: \ sources \ sxs / LimitAccess Now, I do not want to reinstall Windows as this would take a long long time to repair system could not because the user files point to another unit. As if this was the most unusual Any suggestions?