I was really excited for Windows 10, but my system was factory reset, so I had to go back to Windows 8.1. By the time I got back to Windows 8.1, I installed all 100-something updates, hoping Win10 or some prerequisite for it would install. I still have not, seen any sort f update for Windows 10. In fact the only update I see currently is a security update for Internet Explorer. I said, ok, I hear there is an ISO I can download. I thought, ok, I just download xxx.iso, run it, Windows would mount it, and I would be on my way o installation. But of course no. Microsoft wants to make things hard. I had to download some media creation tool that would either allow me to install Windows 10 right now, or make a bootable disk. This would be ok, except for the fact that it does not even start. I get a message box saying:

Setup couldn't start properly. Please reboot your PC and try running Windows 10 setup again

I have tried rebooting several times. Each with no more success. I have tried both 32 and 64 bit editions and both fail. How can I fix this. Everything on Google has been telling me to clean u disk space and I cleared ~40Gb using cleanmgr. I have 407Gb available right now.

  • You have verified you are running Windows 8.1 Update? An in-place upgrade will fail if you are not running Windows 8.1 Update
    – Ramhound
    Jul 30, 2015 at 15:26
  • How do I make sure it is Windows 8.1 update?
    – an earwig
    Jul 30, 2015 at 15:41
  • make sure that you have the right spects (or higher) for windows 10 microsoft.com/en-us/windows/windows-10-specifications that was my problem (i bought more hdd space)
    – user476698
    Aug 1, 2015 at 21:58

3 Answers 3


I found out that the installer was failing due to an earlier attempted installation of Windows 10 that failed (my computer died). In order to fix this, you enter the C:/ drive, show hidden folders, and delete the following:

  • Windows.~BT
  • Windows.~WS
  • Windows.old

Note that you may have to enter safe mode to be able to delete some of these.

  • 1
    there is no need to enter safe mode to delete those files. just run disk cleanup with Administrator privileges and select remove old operating systems and installation files.
    – Keltari
    Jul 30, 2015 at 15:56
  • Tried that, yet they persisted
    – an earwig
    Jul 30, 2015 at 16:14
  • hey i m unable to delete $Windows.~WS folder and this have 2 gigs of file names BITA287.tmp. Aug 4, 2015 at 7:23

Stop the BITS Service to remove/rename the folders in question. No need for safemode.


If deleting those folders didn't help you, run the installer as a different user. your profile might be corrupted.

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