Will store bought Win10 install fix a virus infected Win8.1 machine?

I’m trying to fix my elderly mother-in-law’s Lenovo desktop that will not boot. It’s got Win 8.1 w/Bing and is about 13 months old. (Please skip to last paragraph if you don’t want to read all the background story)

Long story short, this is what happened. It was running fine until yesterday and apparently she got some adware pop-up that prompted her to call a 1-800 number for support. She fell for it, called the number and gave some guy remote access to her computer (grrr… I know, I know). He had access for quite awhile before she called me on another line and I told her to ask what company he works for. He told her “I work for Windows.” I told her to hang up on him and shut down the computer.

So I get there this morning and her comp will not boot. It gets to the Automatic Repair page where I can ‘continue’, ‘troubleshoot’ or ‘turn off pc’, etc. Hitting ‘continue’ just restarts it and comes back to the same page. If I try any of the options under ‘troubleshoot’ it gives me a message saying that only an administrator can make these changes and that there are no administrator accounts on this computer. I tried making a bootable usb from Microsoft but when I click the drive to boot from, it just restarts and comes back to the Automatic Repair page. I tried to edit the boot sequence from the bios but there is no “boot” option in the menu. There is a “startup” option which lets me disable fastboot and such but no option to manually make it boot from the usb drive.

So tell me if I’m wrong but I’m thinking at this point the easiest fix is to just buy a new copy of Win 10 from Bestbuy and do a new install. My question is, will the new install format the HD before installing and completely get rid of all the current viruses? It’s probably a dumb question but in the old days you could just do a ‘format C:’, install the new OS and all was good. Thanks for any advice!



Honorable Member
If you can't select a boot device now, how to select to boot from a W10 installation disk?

I was thinking of taking out the hard disk formatting it on a different machine, next resetting bios by taking out the battery from the motherboard. You may be able to boot up your usb afterwards.

Which Lenovo have you?

Please tell us how you are going.


Windows Forum Team
Staff member
Premium Supporter
Which Lenovo have you?
This is the key question... not all of them will even take WX.


Fantastic Member
Premium Supporter
It's more likely that he had a failed W10 bootable USB flash drive. I just finished putting up a post about all the problems there are with that, specifically the Microsoft Media Creation Tool on their website doesn't work for me. Several other guys here say it works for them no problem. In either case, I had this same problem with Win7 ISO images not working for 2 years--if you already read my post. I'm sure I'll get it working eventually. However, the OP might be better served by creating the bootable DVD W10 disc and attempting it, after running the Microsoft W10 Compatibility Test build into the W10 installer. This will do 2 things for him; (1) it will tell him whether his hardware in the laptop will take a W10 install, and (2) the DVD bootable installer works every single time on a much wider variety of machines (100% on all mine tested).

@rob: I suggest you read the above paragraph for understanding and then look at these suggestions:
#1: Download and create a bootable W10 disc from ISO file from the Microsoft Media Creation Tool page here: Windows 10 ISO
Remember to run the Compatibility Test, and format the hard drive using the option in the Installer. Your observation about the format c:\ command is still valid; but it is normally done in the Windows installer option screen or via a Linux tool such as GPartEd Magic.
NOTE: Most newer Lenovo laptops (built after 2012) have UEFI BIOSes installed, which means you cannot install any kind of bootable usb or dvd disc to bypass the built-in hard drive priority boot, unless you access the UEFI BIOS, and go into options and disable UEFI, and change it to "LEGACY" or similar setting. In addition to this, you will also need to disable the security option on the boot device from "SECURE" to "OFF" or "DISABLED". Without doing these 2 things; even using purchased W10 usb bootable media or dvd bootable media will fail. You are most probably not familiar with this unless you've worked on newer laptops.

#2: Purchase a legit W10 license on either USB or DVD media from Amazon or similar, going to cost you around $100-$200 for this. Disable both boot options in the UEFI BIOS as per above. If you need help, you need to go to Lenovo and download the Owners Manual (in PDF format) directly from the Lenovo stie here: Products - Lenovo Support (US)
The Owners Manual will show you exactly where those 2 settings are. I suggest you do this on a different computer; either a working computer you have, perhaps a laptop you can take with you to your Mom's and do there; or a library or work computer. You only need reference or print out the settings in the UEFI BIOS I mention; if you print it out most sections of UEFI for this are less than 10 pages. So you could print out hardcopy and take over there with you to reference. You'll probably want to do this, as I said; without having the UEFI settings set to enable removable media boot on that Lenovo, you'll never get W10 installed on that laptop even if you spend the $100-$200 and buy licensed Microsoft boxed media (usb or dvd)!!!

Short answer to your question then, is maybe, but probably. We are unaware of any laptops that have UEFI BIOSes failing to install W10. (upgrades is a different story of course!).

If you can't wrap your head around all this, I suggest you take it to your local licensed Computer Pro (A+ license or better) and have this repair for you. This will cost you about $45-$85 in the US. Be prepared to purchase Lenovo Recovery Media for $29-$99 from the Tech or repair shop if you or your Mom don't have the 8.1 Recovery discs or failed to make them prior to your W10 upgrade. That's the very 1st thing we do prior to any upgrade. It's very likely that you also inadvertantly wiped out the Lenovo built-in factory Recovery partition with a W10 clean install, and that option isn't available any longer. (that's worth checking to see if it's still intact). So be prepared for this extra cost if you guys can't provide the Tech with 8.1 discs.:waah: Of course for all this money, you could just go to Dell online, and order a brand new Inspiron 15 Series 3000 laptop for $249 with W10 pre-loaded brand new in-the-box!! Just sayin'..:D

Let us know how it goes or post back if you have any further questions on the upgrade process.


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