You do not need some third party "Tool program" to install Windows 10.
As for a repair file here is an applicable
Microsoft link:
https://support.microsoft.com/en-us...-windows-bd88ffdf-1e8e-34a0-d76f-39a71fb4ed4d
My thought is that some other downloaded program , utility, etc. slipped in some other file or tool; i.e., malware. Or was completely bogus to begin with. Many sites try to lure or otherwise trick you into installing something other than what you intend.>>>
I never did install that program, just downloaded it and now removed it.
Or use a backup to restore the image to before the error began. .\>>>
I never did a backup of win 10 for the short time I had it Ever hear of a small program called "Easy-BCD"? If not, it is what i had installed years ago for a dual system which gives me the option of which OS i wanted to open. You keep mentioning site where i came across this problem. Would u consider that program, a site?
Unfortunately, if the problem is showing up during the dual boot selection process then I believe that a new clean Windows install is going to be needed.
Especially if Win 7 is installed. Obsolete and likely quite vulnerable. Difficult to know which OS may be the "victim" - perhaps both. >>>
Each system is on a separate hd, and i have no problem with win 7....that is how i am able to post here.
https://forums.tomshardware.com/faq/windows-10-clean-install-tutorial.3170366
There may be other ideas and suggestions.