"Something Happened" What Next?

Here are the last few lines of the log file setupact.log. Does this help indicate the likely problem and solution? There is reference to error 0x80004005 but I don't know what this means.

2015-11-17 10:39:14, Info MOUPG CInstallUI::ShowMessageBox: Showing MessageBox
2015-11-17 10:39:15, Error MOUPG CSetupManager::Execute(232): Result = 0x80004005
2015-11-17 10:39:15, Error MOUPG CSetupHost::Execute(371): Result = 0x80004005
2015-11-17 10:39:32, Info MOUPG CInstallUI::Quit: Posted MSG_INSTALLUI_FORCE_QUIT
2015-11-17 10:39:32, Info MOUPG CInstallUI::CInstallUIMessageWindow::ForceQuit
2015-11-17 10:39:32, Info MOUPG Force ending Message pump
2015-11-17 10:39:32, Info MOUPG CInstallUI::ExitInstance
2015-11-17 10:39:32, Info CONX Uninitializing compatibility provider wsc:setup:...
2015-11-17 10:39:32, Info CONX Uninitializing compatibility provider wsc:wica:...
2015-11-17 10:39:33, Info MOUPG SetupUI: Calling PowerClearRequest with type [0x1]...
2015-11-17 10:39:33, Info MOUPG SetupUI: Power request cleared!

Are all of your user data files like My Documents in their default locations on C: drive?

try to extract the ISO to your harddrive and install it. it did bypass the "something happened".
but, unfortunately (for me) it did restart but error at 10% of instalation and then reverting to 10240

I've already copied the ISO to my hard drive, mounted it and ran setup.exe with no success - I got the same error as running setup.exe from the USB installation drive.

Try to Extract The file using Winrar (or any compresion application)
Then run the Setup Directlyit did bypass the "something happened".

Is there anything "unusual" or "customized" about your Windows 8.1 installation? Like 'Users' folder relocated to a different drive? Or 'AppData' folder relocated to a different drive?

There is nothing unusual on my 1 year old Dell laptop - there is only one hard drive having a single user partition with key files in default locations. I have some concerns about the disk partition layout - see https://www.tenforums.com/installatio...tallation.html. I have some more things to try:

1. Disable secure boot
2. Run diagnostics checks - see post 5 this thread
3. Extract ISO directly & run setup.exe - see post 17 this thread
4. Clean install which I was hoping to avoid

TairikuOkami said:

If you have got time, you could try my fix, it will run for about 1-2 hours.

I've now tried running this bat file, removed Classic Shell & Kaspersky Anti Virus but the installation still fails at the same point where Windows is about to restart for the first time.

I've now exhausted all of the common fixes and seek advice what to try next. I'm trying to avoid a clean install if possible since the upgrade process is meant to be 'simple'.

Many people praise the Windows 10 installation process but this has been my worst upgrade experience to date.