Access denied to C: drive serious issues

Following a successful upgrade from my PC running Windows 7 pro 64bit I had a short while running OK. I then had a Notepad window appear on startup together with a sub window saying 'access denied'. Clearing these was no problem but I asked on another forum how to get rid of these messages. I was told to change the access rights on my C: drive and that was when my problems really started.

Now I can't access my C: drive at all and most of my programs transferred from W7 are not working. Whatever I do I get a message saying 'access denied'! My D: drive (partitioned) is fully OK.

I have tried to change the access rights in C: ---- Denied
I have tried to recovery/reset on my W10 ----Failed
I have tried to revert back to W7. It got 1% into making the change and stopped ---- Failed
I even tried option 4 in this link Administrator account - Enable or Disable in Windows 10 - Windows 10 Forums but I got as far as putting REM_SAM into the Load Hive and it said it was already in use ----Failed

Although I have a backup of all my personal folders and files I do not have a backup of my W10 set up. I think I have a backup of my Windows 7 but it is not up to date and I am not really sure how to use it.
I really need help on this one. I have over 20 programs that were successfully transferred over to W10 most of which I need but am not sure how to reload them if they are lost. Most are not now working!

IMO, as it sounds like you've done everything else, including the attempted 'recovery/reset' - have you tried reinstalling 10 from a USB media?

I think you have a virus judging from those pop-ups you got.

Thanks bookfox for that suggestion. How do I go about using a USB to reinstall W10. I did download W10 to get me going in the first place as the W7 upgrade did not work. The file was Windows10Upgrade9252.exe . Would this be the file you mentioned?

Jeff o said:

Thanks bookfox for that suggestion. How do I go about using a USB to reinstall W10. I did download W10 to get me going in the first place as the W7 upgrade did not work. The file was Windows10Upgrade9252.exe . Would this be the file you mentioned?

You need to go to this website.

Code:

https://www.microsoft.com/en-us/software-download/windows10/

Jeff o said:

The file was Windows10Upgrade9252.exe . Would this be the file you mentioned?

Where did you get that file from? I have never seen anything close to that coming from Microsoft.

Sorry about the delay in answering but I have been doing a deep virus scan. A few corrupt files but no big concerns.
I forget where I got the upgrade file from but as I was getting nowhere with the W7 to W10 auto upgrade and MS was far from helpful so I probably asked in my Computer forum and given a link there.
Do I use this again to reinstall W10?

I would download a file from Microsoft instead...

Windows 10 ISO Download - Windows 10 Forums

NavyLCDR said:

I would download a file from Microsoft instead...

Windows 10 ISO Download - Windows 10 Forums

All you need to do, is download the ISO, mount it, and run setup.

Thanks for the links to the ISO download . Looks as if I will have to do it via another PC as I don't have any admin rights on this PC any more.

I have a few questions following any new installation:

1. Will the replacement W10 be the pro 64bit version as I have now?
2. I am using Windows Live Mail ( in W10) that has my email addresses and stored emails. Will I be able to install WLM into the new build? And how can I get all my currently stored old email mails transferred?
3. I am also successfully using several other programs including Office 2003 & Photoshop CS2, both of which I have the correct keys. Will I be able to load and use these programs OK?