Sometimes Windows gets stuck during upgrade - the spinny dots move, but no progress is made. If you force a reboot then Windows will roll the upgrade back, but in order to figure out why the problem is happening, it is very useful to grab a memory dump of the problem while the upgrade is in the stuck state.
To do this, follow the steps on Forcing a System Crash from the Keyboard (reworded here)
- Prior to the upgrade, use Registry Editor to create the following two values
- Within the HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\i8042prt\Parameters key, create a REG_DWORD value named CrashOnCtrlScroll, and set it to 1
- Within the HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\kbdhid\Parameters key, create a REG_DWORD value named CrashOnCtrlScroll, and set it to 1
- Reboot so that the registry change takes effect
- You should now be able to force a Blue Screen of Death or Green Screen of Death, at will, by holding down the rightmost Ctrl key and pressing the Scroll Lock key twice; the stop code will be MANUALLY_INITIATED_CRASH and the resulting memory dump will be at C:\Windows\MEMORY.DMP
- Attempt the upgrade and let it get to the point where it gets stuck
- Now, at the key point, hold down the rightmost Ctrl key and press the Scroll Lock key twice - you should see the Blue Screen of Death or Green Screen of Death
- Let it create the memory dump and roll back
- As described in Resolution procedures, the rollback process will move the C:\Windows\MEMORY.DMP file to C:\$Windows.~bt\Sources\Rollback\setupmem.dmp (note that C:\$Windows.~bt is a hidden folder)
- Depending on your memory dump settings, the file may be quite large, but even if so, it should compress well
Once you have gotten the dump file, you can go back into Registry Editor and delete the two CrashOnCtrlScroll values, then reboot.