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#11
I have Win7 Pro SP1 on my Ontario computer and Win 8.1 on my Florida one. I installed Win10 Build 9926 on a new 256 GB SSD and brought the SSD when I came back from FL and plugged it in to my computer here and have been doing upgrades up until 10122 so far. Unplugged the Win7 drive so as to not have any funny business. I don't intend to give up my license for Win7 so won't be upgrading it. I have another SSD somewhere and if I can find it, I will install Win7 SP1 and try to upgrade it to Win10. You're got me curious now.
24GB ram may be the problem. Try removing all but 4GB (or 8GB is has to be paired) and see what happens. You can put all the ram back after the install if it works.
This is a grasping at straws type of idea, as the TP's move closer to the RTM could an upgrade through windows update be dependent upon a previous installation of the earlier TP? I've only used WU to install new versions with little problems noted other than how long it takes.
It takes a long time, I have an 18M connection and between that and the install it's probably 4 hours or more. After the first time taking that long I now wait until the new TP is being installed and usually go to bed. I use WMware player freeware ver. 7.1.0 build-2496824 on a Win7 Home Premium SP1 host.
Maybe try installing an earlier version and then trying the upgrade. I've reviewed the thread and don't think I've seen whether you've tried it that way. What a PIA you've been through so far, jeez WU is how this OS is supposed to be installed so they really need to get that part working.